0001558370-24-001229 | 10-K | XBRL Viewer

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Derivatives - Net derivatives as reflected on the balance sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	$ 833	$ 2,707
Other current assets
Derivatives, Fair Value [Line Items]
Current asset representing cash collateral posted	600	0
Heating oil and coal \| Other current assets
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	998	$ 2,707
Coal Contract \| Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	$ (165)

Risk Concentrations

12 Months Ended

Dec. 31, 2023

Risk Concentrations

Risk Concentrations

20. Risk Concentrations

Credit Risk and Major Customers

The Company has a formal written credit policy that establishes procedures to determine creditworthiness and credit limits for trade customers and counterparties in the over-the-counter coal market. Generally, credit is extended based on an evaluation of the customer’s financial condition. Collateral is not generally required, unless credit cannot be established. Credit losses are provided for in the financial statements and historically have been minimal.

The Company markets its thermal coal principally to domestic and foreign electric utilities and its metallurgical coal to domestic and foreign steel producers. As of December 31, 2023 and 2022, accounts receivable from sales of thermal coal of $67.2 million and $94.1 million, respectively, represented 25% and 40% of total trade receivables at each date. As of December 31, 2023 and 2022, accounts receivable from sales of metallurgical-quality coal of $206.3 million and $142.9 million, respectively, represented 75% and 60% of total trade receivables at each date.

The Company uses shipping destination as the basis for attributing revenue to individual countries. Because title may transfer on brokered transactions at a point that does not reflect the end usage point, they are reflected as exports,

and attributed to an end delivery point if that knowledge is known to the Company. The Company’s foreign revenues by geographical location are as follows:


	Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,
	2023		2022		2021
(In thousands)
Europe	$	696,975	$	939,955	$	592,702
Asia		935,158		1,210,855		446,724
Central and South America		136,423		160,642		109,613
Africa		4,971		—		—
Total	$	1,773,527	$	2,311,452	$	1,149,039

The Company is committed under long-term contracts to supply thermal coal that meets certain quality requirements at specified prices. These prices are generally adjusted based on market indices. Quantities sold under some of these contracts may vary from year to year within certain limits at the option of the customer based on their requirements. The Company sold approximately 75 million tons of coal in 2023. Approximately 75% of this tonnage (representing approximately 46% of the Company’s revenues) was sold under long-term contracts (contracts having a term of greater than one year). Long-term contracts range in remaining life from one to four years.

Third-party sources of coal

The Company purchases coal from third parties that it sells to customers. Factors beyond the Company’s control could affect the availability of coal purchased by the Company. Disruptions in the quantities of coal purchased by the Company could impair its ability to fill customer orders or require it to purchase coal from other sources at prevailing market prices in order to satisfy those orders.

Transportation

The Company depends upon barge, rail, truck and belt transportation systems to deliver coal to its customers. Disruption of these transportation services due to weather-related problems, mechanical difficulties, strikes, lockouts, bottlenecks, and other events could temporarily impair the Company’s ability to supply coal to its customers. In the past, disruptions in rail service have resulted in missed shipments and production interruptions.

Accumulated Other Comprehensive Income (Loss)

12 Months Ended

Dec. 31, 2023

Accumulated Other Comprehensive Income (Loss).

Accumulated Other Comprehensive Income (Loss)

3. Accumulated Other Comprehensive Income (Loss)

The following items are included in accumulated other comprehensive income:


			Pension,
			Postretirement				Accumulated
			and Other Post-				Other
	Derivative		Employment		Available-for-		Comprehensive
	Instruments		Benefits		Sale Securities		Income (loss)

	(In thousands)
January 1, 2022	$	(1,763)	$	16,103	$	(182)	$	14,158
Unrealized gains (losses)		223		61,041		(21)		61,243
Amounts reclassified from accumulated other comprehensive income (loss)		1,540		(3,111)		182		(1,389)
Tax effect		—		(12,548)		(35)		(12,583)
Balances at December 31, 2022	$	—	$	61,485	$	(56)	$	61,429
Unrealized (losses) gains		—		(8,506)		9		(8,497)
Amounts reclassified from accumulated other comprehensive income (loss)		—		(15,858)		30		(15,828)
Tax effect		—		1,662		16		1,678
Balances at December 31, 2023	$	—	$	38,783	$	(1)	$	38,782

The following amounts were reclassified out of accumulated other comprehensive income (loss) during the respective periods:


	December 31,		December 31,		Line Item in the Condensed Consolidated
Details About AOCI Components	2023		2022		Income Statements

Interest rate hedges	$	—	$	(112)	Interest expense
Interest rate hedges (ineffective portion)		—		(1,428)	Net loss resulting from early retirement of debt
		—		—	Provision for income taxes
	$	—	$	(1,540)	Net of tax

Pension, postretirement and other post-employment benefits
Amortization of actuarial gains, net ¹	$	11,208	$	2,193	Non-service related pension and postretirement benefit credits (costs)
Amortization of prior service credits		98		147	Non-service related pension and postretirement benefit credits
Pension Termination/Settlement		4,552		771	Non-service related pension and postretirement benefit credits (costs)
	$	15,858	$	3,111	Total before tax
		(1,662)		(674)	Provision for income taxes
	$	14,196	$	2,437	Net of tax

Available-for-sale securities ²	$	(30)	$	(182)	Interest and investment income
		16		39	Provision for income taxes
	$	(14)	$	(143)	Net of tax

¹ Production-related benefits and workers’ compensation costs are included in costs of sales.

² The gains and losses on sales of available-for-sale-securities are determined on a specific identification basis.

Equity Method Investments and Membership Interests in Joint Ventures (Schedule of Equity Method Investments) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Beginning Balance	$ 17,267
Ending Balance	22,815	$ 17,267
DTA
Investments in and Advances to Affiliates, at Fair Value [Roll Forward]
Beginning Balance	17,267	15,403
Advances to (distributions from) affiliates, net	17,345	9,575
Equity in comprehensive income (loss)	(11,797)	(7,711)
Ending Balance	$ 22,815	$ 17,267

Cover Page - USD ($) $ in Millions	12 Months Ended
Cover Page - USD ($) $ in Millions	Dec. 31, 2023	Feb. 01, 2024	Jun. 30, 2023
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Entity File Number	1-13105
Entity Registrant Name	Arch Resources, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	43-0921172
Entity Address, Address Line One	1 CityPlace Drive
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	St. Louis
Entity Address, State or Province	MO
Entity Address, Postal Zip Code	63141
City Area Code	314
Local Phone Number	994-2700
Title of 12(b) Security	Common Stock, $.01 par value
Trading Symbol	ARCH
Security Exchange Name	NYSE
Entity Well Known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business Company	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 2,052.1
Entity Common Stock, Shares Outstanding (in shares)		18,360,691
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement to be filed with the Securities and Exchange Commission in connection with the 2023 annual stockholders’ meeting are incorporated by reference into Part III of this Form 10-K.
Auditor Firm ID	42
Auditor Name	Ernst & Young LLP
Auditor Location	St. Louis, Missouri
Entity Central Index Key	0001037676
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false

Workers' Compensation Expense (Schedule of Expected Future Payments) (Details) - Workers Compensation Obligation $ in Thousands	Dec. 31, 2023 USD ($)
Expected Future Payments
2024	$ 12,837
2025	13,634
2026	13,750
2027	14,186
2028	14,564
Next 5 years	79,731
Total	$ 148,702

Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2023

Asset Retirement Obligation

Schedule of Change in Asset Retirement Obligation


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
(In thousands)
Balance at beginning of period (including current portion)	$	244,368	$	214,453
Accretion expense		21,170		17,721
Adjustments to the liability from changes in estimates		17,747		25,914
Reclamation work completed		(21,456)		(13,720)
Balance at period end	$	261,829	$	244,368
Current portion included in accrued expenses		(6,089)		(8,632)
Noncurrent liability	$	255,740	$	235,736

Investments in Available-for-Sale securities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Investments in Available-for-Sale Securities
Unrealized losses owned for less than 12 months	$ 2.2	$ 22.6
Unrealized losses owed for over a year	$ 2.3	$ 0.0

Stock-Based Compensation and Other Incentive Plans (Restricted Stock Unit Activity) (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Time Based Awards
Restricted Stock Common Shares
Outstanding at beginning of period (in shares) \| shares	359
Granted (in shares) \| shares	57
Forfeited/Canceled (in shares) \| shares	(1)
Vested (in shares) \| shares	(186)
Outstanding at end of period (in shares) \| shares	229
Weighted Average Grant Date Fair Value
Outstanding weighted average grant date fair value at beginning of period (in dollars per share) \| $ / shares	$ 74.14
Granted (in dollars per share) \| $ / shares	$ 136.55
Forfeited/Canceled (in dollars per share) \| $ / shares	98.82
Vested (in dollars per share) \| $ / shares	$ 70.56
Outstanding weighted average grant date fair value at end of period (in dollars per share) \| $ / shares	$ 92.41
Performance Based Awards
Restricted Stock Common Shares
Outstanding at beginning of period (in shares) \| shares	407
Granted (in shares) \| shares	221
Forfeited/Canceled (in shares) \| shares	(1)
Vested (in shares) \| shares	(324)
Outstanding at end of period (in shares) \| shares	303
Weighted Average Grant Date Fair Value
Outstanding weighted average grant date fair value at beginning of period (in dollars per share) \| $ / shares	$ 74.68
Granted (in dollars per share) \| $ / shares	$ 95.83
Forfeited/Canceled (in dollars per share) \| $ / shares	145.11
Vested (in dollars per share) \| $ / shares	$ 48.45
Outstanding weighted average grant date fair value at end of period (in dollars per share) \| $ / shares	$ 117.85

Derivatives - Effects of derivatives on measures of financial performance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of coal derivatives and coal trading activities, net total	$ (1,572)	$ (1,274)	$ 2,392
Not Designated as Hedging Instrument \| Coal Contract \| Change in fair value of coal derivatives and coal trading activities, net
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives	(1,572)	(1,274)	2,392
Not Designated as Hedging Instrument \| Coal Contract \| Other operating (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives	6,254	(42,068)	$ (27,464)
Not Designated as Hedging Instrument \| Heating oil - diesel purchases \| Other operating (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Heating oil realized and unrealized gains and losses	$ (4,079)	$ 8,309

Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Taxes

Schedule of Components of Income Tax Expense (Benefit)


		Year Ended		Year Ended	Year Ended
		December 31,		December 31,	December 31,
		2023		2022	2021
(In thousands)
Current:
Federal	$	106	$	(30,107)	$	1,525
State		317		204		342
Total current	$	423	$	(29,903)	$	1,867
Deferred:
Federal	$	85,002	$	(209,130)	$	7
State		2,089		(12,893)		—
Total deferred	$	87,091	$	(222,023)	$	7
Provision for (benefit from) income taxes	$	87,514	$	(251,926)	$	1,874

Schedule of Effective Income Tax Rate Reconciliation


	Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,
	2023		2022		2021

Income tax provision at statutory rate	$	115,826	$	226,587	$	71,284
Percentage depletion and other permanent items		(30,585)		(52,647)		(29,392)
State taxes, net of effect of federal taxes		2,725		2,988		16,490
Change in valuation allowance		(879)		(420,688)		(69,603)
Other, net		427		(8,166)		13,095
Provision for (benefit from) income taxes	$	87,514	$	(251,926)	$	1,874

Schedule of Deferred Tax Assets and Liabilities

Significant components of the Company’s deferred tax assets and liabilities that result from carryforwards and temporary differences between the financial statement basis and tax basis of assets and liabilities are summarized as follows:


	December 31,		December 31,
	2023		2022
(In thousands)
Deferred tax assets:
Tax loss carryforwards	$	157,648	$	219,302
Tax credit carryforwards		1,584		1,656
Investment in partnerships		24,933		39,999
Other		28,070		38,362
Gross deferred tax assets	$	212,235	$	299,319
Valuation allowance		(82,825)		(83,704)
Total deferred tax assets	$	129,410	$	215,615
Deferred tax liabilities:
Plant and equipment		1,075		1,245
Convertible Notes		—		75
Other		4,311		4,825
Total deferred tax liabilities	$	5,386	$	6,145
Net deferred tax asset	$	124,024	$	209,470

Summary of Income Tax Contingencies


	(In thousands)
Balance at December 31, 2020	$	48,116
Additions based on tax positions to the current year		3,467
Additions for tax positions related to the prior year		3,931
Reductions for tax positions of prior years		(2,868)
Reductions as a result of lapses in the statute of limitations		(3,683)
Balance at December 31, 2021		48,963
Additions for tax positions related to the current year		5,446
Additions for tax positions related to the prior year		768
Reductions for tax positions of prior years		(125)
Reductions as a result of lapses in the statute of limitations		(36,988)
Balance at December 31, 2022		18,064
Additions based on tax positions related to the current year		3,019
Additions for tax positions related to the prior year		731
Increases for tax positions of prior years		1,485
Reductions as a result of lapses in the statute of limitations		(2,732)
Balance at December 31, 2023	$	20,567

Risk Concentrations (Schedule of Foreign Revenues) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Concentration Risk [Line Items]
Revenues	$ 3,145,843	$ 3,724,593	$ 2,208,042
Seaborne Revenue
Concentration Risk [Line Items]
Revenues	1,773,527	2,311,452	1,149,039
Europe \| Seaborne Revenue
Concentration Risk [Line Items]
Revenues	696,975	939,955	592,702
Asia \| Seaborne Revenue
Concentration Risk [Line Items]
Revenues	935,158	1,210,855	446,724
Central and South America \| Seaborne Revenue
Concentration Risk [Line Items]
Revenues	136,423	$ 160,642	$ 109,613
Africa \| Seaborne Revenue
Concentration Risk [Line Items]
Revenues	$ 4,971

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 924
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479941/924-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-4

+ Details

Debt and Financing Arrangements - Long term debt (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Nov. 30, 2020
Debt Instrument [Line Items]
Long-term debt	$ 142,106
Debt issuance costs	(1,511)	$ (2,929)
Total	140,595	174,276
Less: current maturities of debt	35,343	57,988
Long-term debt	105,252	116,288
Debt instrument, face amount			$ 155,300
Term loan due 2024
Debt Instrument [Line Items]
Long-term debt	3,502	6,502
Debt instrument, face amount	3,500
Tax Exempt Bonds
Debt Instrument [Line Items]
Long-term debt	98,075	98,075
Debt instrument, face amount	98,100
Convertible Debt.
Debt Instrument [Line Items]
Long-term debt		13,156
Other Debt
Debt Instrument [Line Items]
Long-term debt	$ 40,529	$ 59,472

Inventories

12 Months Ended

Dec. 31, 2023

Inventories

Inventories

5. Inventories

Inventories consist of the following:


	December 31,		December 31,
	2023		2022

	(In thousands)
Coal	$	99,174	$	96,954
Repair parts and supplies		145,087		126,061
	$	244,261	$	223,015

The repair parts and supplies are stated net of an allowance for slow-moving and obsolete inventories of $1.6 million at December 31, 2023 and $2.4 million at December 31, 2022.

Taxes (Schedule of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Tax loss carryforwards	$ 157,648	$ 219,302
Tax credit carryforwards	1,584	1,656
Investment in partnerships	24,933	39,999
Other	28,070	38,362
Gross deferred tax assets	212,235	299,319
Valuation allowance	(82,825)	(83,704)
Total deferred tax assets	129,410	215,615
Deferred tax liabilities:
Plant and equipment	1,075	1,245
Convertible Notes		75
Other	4,311	4,825
Total deferred tax liabilities	5,386	6,145
Net deferred tax asset	$ 124,024	$ 209,470

Derivatives

12 Months Ended

Dec. 31, 2023

Derivatives

Derivatives

8. Derivatives

Diesel fuel price risk management

The Company is exposed to price risk with respect to diesel fuel purchased for use in its operations. The Company anticipates purchasing approximately 30 to 35 million gallons of diesel fuel for use in its operations during 2024. To protect the Company’s cash flows from increases in the price of diesel fuel, the Company has purchased heating oil call options. At December 31, 2023, the Company had protected the price of expected diesel fuel purchases for 2024 with approximately 24 million gallons of heating oil call options with an average strike price of $2.96 per gallon. These positions are not designated as hedges for accounting purposes, and therefore, changes in the fair value are recorded immediately to earnings.

Coal risk management positions

The Company may sell or purchase forward contracts, swaps and options in the over-the-counter coal market in order to manage its exposure to coal prices. The Company has exposure to the risk of fluctuating coal prices related to forecasted sales or purchases of coal or to the risk of changes in the fair value of a fixed price physical sales contract. Certain derivative contracts may be designated as hedges of these risks.

At December 31, 2023, the Company held approximately 7,000 tons of coal derivatives for risk management purposes that are expected to settle in 2024.

Tabular derivatives disclosures

The Company has master netting agreements with all of its counterparties which allow for the settlement of contracts in an asset position with contracts in a liability position in the event of default or termination. Such netting arrangements reduce the Company’s credit exposure related to these counterparties. For classification purposes, the Company records the net fair value of all the positions with a given counterparty as a net asset or liability in the Consolidated Balance Sheets. The amounts shown in the table below represent the fair value position of individual contracts, and not the net position presented in the accompanying Consolidated Balance Sheets.

The fair value and location of derivatives reflected in the accompanying Consolidated Balance Sheets are as follows:


	December 31, 2023						December 31, 2022
Fair Value of Derivatives	Asset		Liability				Asset		Liability
(In thousands)	Derivative		Derivative				Derivative		Derivative
Derivatives Not Designated as Hedging Instruments
Heating oil -- diesel purchases		998		—				1,300		—
Coal -- risk management		—		(165)				1,407		—
Total	$	998	$	(165)			$	2,707	$	—
Total derivatives	$	998	$	(165)			$	2,707	$	—
Effect of counterparty netting		—		—				—		—
Net derivatives as classified in the balance sheets	$	998	$	(165)	$	833	$	2,707	$	—	$	2,707


Fair Value of Derivatives		December 31,		December 31,
(In thousands)		2023		2022
Net derivatives as reflected on the balance sheets (in thousands)
Heating Oil and coal	Other current assets	$	998	$	2,707
Coal	Accrued expenses and other current liabilities		(165)		—
		$	833	$	2,707

The Company had a current asset representing cash collateral posted to a margin account for derivative positions primarily related to coal derivatives of $0.6 million at December 31, 2023. At December 31, 2022, the current open derivative positions were non-margined. This amount is not included with the derivatives presented in the table above and is included in “other current assets” in the accompanying Consolidated Balance Sheets.

The effects of derivatives on measures of financial performance are as follows:

Derivatives Not Designated as Hedging Instruments (in thousands)

For the noted periods,


		Gain (Loss) Recognized
		Year Ended		Year Ended		Year Ended
		December 31,		December 31,		December 31,
		2023		2022		2021
Coal trading— realized and unrealized	⁽³⁾	$	—	$	—	$	—
Coal risk management— unrealized	⁽³⁾		(1,572)		(1,274)		2,392
Natural gas trading — realized and unrealized	⁽³⁾		—		—		—
Change in fair value of coal derivatives and coal trading activities, net total		$	(1,572)	$	(1,274)	$	2,392

Coal risk management — realized	⁽⁴⁾	$	6,254	$	(42,068)	$	(27,464)
Heating oil — diesel purchases	⁽⁴⁾	$	(4,079)	$	8,309	$	—

Location in Consolidated Statements of Operations:

(1)

— Revenues

(2)

— Cost of sales

(3)

— Change in fair value of coal derivatives, net

(4)

— Other operating income, net

Accounting Policies

12 Months Ended

Dec. 31, 2023

Accounting Policies

Accounting Policies

2. Accounting Policies

The accompanying consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for financial reporting and U.S. Securities and Exchange Commission regulations.

Accounting Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and revenues and expenses in the accompanying consolidated financial statements and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates.

Cash and Cash Equivalents

Cash and cash equivalents are stated at cost. Cash equivalents consist of highly-liquid investments with an original maturity of three months or less when purchased and investments in commercial paper which the Company classifies as cash and cash equivalents.

Restricted Cash

Amounts included in restricted cash represent required deposits for a performance bid bond for a potential customer for $1.1 million as of both December 31, 2023 and 2022, respectively.

Accounts Receivable

Accounts receivable are recorded at amounts that are expected to be collected, based on past collection history, the economic environment and specified risks identified in the receivables portfolio.

Inventories

Coal and supplies inventories are valued at the lower of average cost or market. Coal inventory costs include labor, supplies, equipment costs, transportation costs incurred prior to the transfer of title to customers and operating overhead. The costs of removing overburden, called stripping costs, incurred during the production phase of the mine are considered variable production costs and are included in the cost of the coal extracted during the period the stripping costs are incurred.

Investments and Membership Interests in Joint Ventures

Investments and membership interests in joint ventures are accounted for under the equity method of accounting if the Company has the ability to exercise significant influence, but not control, over the entity. The Company’s share of the entity’s income or loss is reflected in “Other operating (income) expense, net” in the Consolidated Income Statements. Information about investment activity is provided in Note 7, “Equity Method Investments and Membership Interests in Joint Ventures” to the Consolidated Financial Statements.

Investments in debt securities are classified as available-for-sale and are recorded at their fair values. Unrealized gains and losses on these investments are recorded in other comprehensive income or loss. A decline in the value of an investment that is considered other-than-temporary would be recognized in operating expenses.

Exploration Costs

Costs to acquire permits for exploration activities are capitalized. Drilling and other costs related to locating coal deposits and evaluating the economic viability of such deposits are expensed as incurred.

Prepaid Royalties

Leased mineral rights are often acquired through royalty payments. When royalty payments represent prepayments recoupable against royalties owed on future revenues from the underlying coal, they are recorded as a prepaid asset, with amounts expected to be recouped within one year classified as current. When coal from these leases is sold, the royalties owed are recouped against the prepayment and charged to cost of sales. An impairment charge is recognized for prepaid royalties that are not expected to be recouped.

Property, Plant and Equipment

Plant and Equipment

Plant and equipment were recorded at fair value at emergence during fresh start accounting; subsequent purchases of property, plant and equipment have been recorded at cost. Interest costs incurred during the construction period for major asset additions are capitalized. The Company did not capitalize interest costs during the years ended December 31, 2023, and 2022, respectively. Expenditures that extend the useful lives of existing plant and equipment or increase the productivity of the asset are capitalized. The cost of maintenance and repairs that do not extend the useful life or increase the productivity of the asset is expensed as incurred.

Preparation plants and loadouts are depreciated using the units-of-production method over the estimated recoverable reserves, subject to a minimum level of depreciation. Other plant and equipment are depreciated principally using the straight-line method over the estimated useful lives of the assets, limited by the remaining life of the mine. The useful lives of mining equipment, including longwalls, draglines and shovels, range from 1 to 16 years. The useful lives of buildings and leasehold improvements generally range from 5 to 20 years.

Deferred Mine Development

Costs of developing new mines or significantly expanding the capacity of existing mines are capitalized and amortized using the units-of-production method over the estimated recoverable reserves that are associated with the property being benefited. Costs may include construction permits and licenses; mine design; construction of access roads, shafts, slopes and main entries; and removing overburden to access reserves in a new pit. Additionally, deferred mine development includes the asset cost associated with asset retirement obligations. Coal sales revenue related to incidental production during the development phase is recorded as coal sales revenue with an offset to cost of coal sales based on the estimated cost per ton sold for the mine when the asset is in place for its intended use.

Coal Lands and Mineral Rights

Rights to coal reserves may be acquired directly through governmental or private entities. A significant portion of the Company’s coal reserves are controlled through leasing arrangements. Lease agreements are generally long-term in nature (original terms range from 10 to 50 years), and substantially all of the leases contain provisions that allow for automatic extension of the lease term providing certain requirements are met. Leases of mineral reserves and related land leases are exempt from the provisions of the leasing standard.

The net book value of the Company’s coal interests was $215.6 million and $239.4 million at December 31, 2023 and 2022, respectively. Payments to acquire royalty lease agreements and lease bonus payments are capitalized as a cost of the underlying mineral reserves and depleted over the life of proven and probable reserves. Coal lease rights are depleted using the units-of-production method, and the rights are assumed to have no residual value.

The Company currently does not have any future lease bonus payments.

Depreciation, depletion and amortization

The depreciation, depletion and amortization related to long-lived assets is reflected in the Consolidated Income Statements as a separate line item. No depreciation, depletion or amortization are included in any other operating cost categories.

Impairment

If facts and circumstances suggest that the carrying value of a long-lived asset or asset group may not be recoverable, the asset or asset group is reviewed for potential impairment. If this review indicates that the carrying amount of the asset will not be recoverable through projected undiscounted cash flows generated by the asset and its related asset group over its remaining life, then an impairment loss is recognized by reducing the carrying value of the asset to its fair value. The Company may, under certain circumstances, idle mining operations in response to market conditions or other factors. Because an idling is not a permanent closure, it is not considered an automatic indicator of impairment.

Deferred Financing Costs

The Company capitalizes costs incurred in connection with new borrowings, the establishment or enhancement of credit facilities and the issuance of debt securities. These costs are amortized as an adjustment to interest expense over the life of the borrowing or term of the credit facility using the effective interest method. Debt issuance costs related to a recognized liability are presented in the balance sheet as a direct reduction from the carrying amount of that liability whereas debt issuance costs related to a credit facility with no balance outstanding are shown as an asset. The unamortized balance of deferred financing costs shown as an asset was $1.0 million at December 31, 2023, with $0.6 million classified as current; the unamortized balance of deferred financing costs shown as an asset at December 31, 2022 was $1.6 million with $0.6 million classified as current. The current amounts are classified within “Other current assets” and the noncurrent amounts are classified within “Other noncurrent assets.” For information on the unamortized balance of deferred financing fees related to outstanding debt, see Note 10, “Debt and Financing Arrangements” to the Consolidated Financial Statements.

Revenue Recognition

Revenues include sales to customers of coal produced at Company operations and coal purchased from third parties. The Company recognizes revenue at the time risk of loss passes to the customer at contracted amounts. Transportation costs are included in cost of sales and amounts billed by the Company to its customers for transportation are included in revenues. Control of the goods may transfer and revenue may be recognized before, during or subsequent to the period in which final average pricing is determined. For all metallurgical coal sales under average pricing contracts where pricing is not finalized when revenue is recognized, revenue is recorded based on estimated consideration to be received at the date of the sale with reference to metallurgical coal price assessments.

Other Operating (Income) Expense, net

Other operating (income) expense, net in the accompanying Consolidated Income Statements reflects income and expense from sources other than physical coal sales, including: contract settlements; royalties earned from properties leased to third parties; income from equity investments (Note 7, “Equity Method Investments and Membership Interests in Joint Ventures”); non-material gains and losses from divestitures and dispositions of assets; and realized gains and losses on derivatives that do not qualify for hedge accounting and are not held for trading purposes (Note 8, “Derivatives”); and land management expenses.

Asset Retirement Obligations

The Company’s legal obligations associated with the retirement of long-lived assets are recognized at fair value at the time the obligations are incurred. Accretion expense is recognized through the expected settlement date of the obligation. Obligations are incurred at the time development of a mine commences for underground and surface mines or construction begins for support facilities, refuse areas and slurry ponds. The obligation’s fair value is determined using a discounted cash flow technique and is based upon permit requirements and various estimates and assumptions that would be used by market participants, including estimates of disturbed acreage, reclamation costs and assumptions regarding equipment productivity. Upon initial recognition of a liability, a corresponding amount is capitalized as a component of the carrying value of the related long-lived asset.

The Company reviews its asset retirement obligation at least annually and makes necessary adjustments for permit changes as granted by state authorities and for revisions of estimates of the amount and timing of costs. For ongoing operations, adjustments to the liability result in an adjustment to the corresponding asset. For idle operations, adjustments to the liability are recognized as income or expense in the period the adjustment is recorded. Any difference between the recorded obligation and the actual cost of reclamation is recorded in profit or loss in the period the obligation is settled. See additional discussion in Note 12, “Asset Retirement Obligations” to the Consolidated Financial Statements.

Loss Contingencies

The Company accrues for cost related to contingencies when a loss is probable and the amount is reasonably determinable. Disclosure of contingencies is included in the financial statements when it is at least reasonably possible that a material loss or an additional material loss in excess of amounts already accrued may be incurred. The amount accrued represents the Company’s best estimate of the loss, or, if no best estimate within a range of outcomes exists, the minimum amount in the range.

Derivative Instruments

The Company generally utilizes derivative instruments to manage exposures to commodity prices and interest rate risk on long-term debt. Derivative financial instruments are recognized on the balance sheet at fair value. Certain coal contracts may meet the definition of a derivative instrument, but because they provide for the physical purchase or sale of coal in quantities expected to be used or sold by the Company over a reasonable period in the normal course of business, they are not recognized on the balance sheet.

See Note 8, “Derivatives” to the Consolidated Financial Statements for further disclosures related to the Company’s derivative instruments.

Fair Value

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly hypothetical transaction between market participants at a given measurement date. Valuation techniques used must maximize the use of observable inputs and minimize the use of unobservable inputs. See Note 13, “Fair Value Measurements” to the Consolidated Financial Statements for further disclosures related to the Company’s recurring fair value estimates.

Income Taxes

Deferred income taxes are provided for temporary differences arising from differences between the financial statement and tax basis of assets and liabilities existing at each balance sheet date using enacted tax rates anticipated to be in effect when the related taxes are expected to be paid or recovered. A valuation allowance is established if it is more likely than not that a deferred tax asset will not be realized. Management reassesses the ability to realize its deferred tax assets annually in the fourth quarter or when circumstances indicate that the ability to realize deferred tax assets has changed. In determining the need for a valuation allowance, the Company considers projected realization of tax benefits based on expected levels of future taxable income, available tax planning strategies and the reversal of temporary differences. As it relates to changes in accumulated other comprehensive income (loss), the Company’s policy is to release tax effects from accumulated other comprehensive income (loss) when the underlying components affect earnings.

Benefits from tax positions that are uncertain are not recognized unless the Company concludes that it is more likely than not that the position would be sustained in a dispute with taxing authorities, should the dispute be taken to the court of last resort. The Company would measure any such benefit at the largest amount of benefit that is greater than 50% likely of being realized upon settlement with taxing authorities.

See Note 11, “Taxes” to the Consolidated Financial Statements for further disclosures about income taxes.

Benefit Plans

In February 2022, the Board of Directors approved the termination of the Company’s Cash Balance Pension Plan. The Company has executed plan amendments regarding the termination and filed an Application for Determination for Terminating Pension Plan with the Internal Revenue Service (“IRS”), which was approved by the IRS during the first quarter of 2023. The Company also prepared and filed appropriate notices and documents related to the Pension Plan's termination and wind-down with the Pension Benefit Guaranty Corporation (“PBGC”). To complete the termination of the plan, the Company made a $3.2 million cash contribution into the plan in order to complete lump sum payments and to purchase annuity contracts for plan participants. An immaterial gain was recognized on the plan termination, which is reflected in the Consolidated Income Statements line item “Non-service related pension and postretirement benefits credits (costs)”. The Company no longer administers or pays the retirement benefits of the Company’s Cash Balance Pension Plan going forward.

Stock-Based Compensation

The compensation cost of all stock-based awards is determined based on the grant-date fair value of the award, and is recognized over the requisite service period. The grant-date fair value of restricted stock awards with a market condition is determined using a Monte Carlo simulation. Compensation cost for an award with performance conditions is accrued if it is probable that the conditions will be met. The Company accounts for forfeitures as they occur. See further discussion in Note 15, “Stock-Based Compensation and Other Incentive Plans” to the Consolidated Financial Statements.

Recently Adopted Accounting Guidance

In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity's Own Equity (Subtopic 815-40)—Accounting for Convertible

Instruments and Contracts in an Entity's Own Equity. ASU 2020-06 reduces the number of accounting models for convertible debt instruments. Additionally, ASU 2020-06 amends the diluted earnings per share calculation for convertible instruments by requiring the use of the if-converted method. The if-converted method assumes the conversion of convertible instruments occurs at the beginning of the reporting period and diluted weighted average shares outstanding includes the common shares issuable upon conversion of the convertible instruments. ASU 2020-06 is effective for public business entities, for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. The Company adopted ASU 2020-06 on January 1, 2022 under the modified retrospective approach.

Upon issuance of the Company's $155.3 million principal amount of 5.25% convertible senior notes due 2025 (the "Convertible Notes" or “Convertible Debt”) in November 2020, the Company bifurcated the debt and equity components of the Convertible Notes to long-term debt and additional paid-in capital in its consolidated balance sheet. The amount recorded to additional paid-in capital represented a debt discount that was being amortized to interest expense over the life of the Convertible Notes. As part of the adoption of ASU 2020-06, the Company (i) reversed the equity component recorded to additional paid-in capital of $39.2 million, (ii) recorded a cumulative effect of the adoption of ASU 2020-06 of $6.7 million to retained earnings, representing a reversal of the debt discount that was amortized to interest expense, and (iii) recorded an offsetting increase in debt. See Note 10, “Debt and Financing Arrangements” for additional information.

Additionally, upon adoption of ASU 2020-06, the treasury stock method utilized by the Company to calculate earnings per share through December 31, 2021 is no longer permitted. Accordingly, the Company has transitioned to the if-converted method utilizing the modified retrospective approach. For the year ended December 31, 2022, under the previous treasury stock method, the diluted earnings per share would have been approximately $65.28. As a result of the adoption of ASU 2020-06, diluted earnings per share decreased by $1.40 for the year ended December 31, 2022. During 2023, the Company repurchased the remaining Convertible Notes with a principal amount of $13.2 million for aggregate consideration consisting of $58.4 million in cash.

Recently Adopted Accounting Guidance Not Yet Effective

In November 2023, the FASB issued ASU 2023-07 Segment Reporting – Improving Reportable Segment Disclosures (Topic 280). The update is intended to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant expenses. The ASU requires disclosure to include significant segment expenses that are regularly provided to the chief operating decision maker (CODM), a description of other segment items by reportable segment, and any additional measures of a segment’s profit or loss used by the CODM when deciding how to allocate resources. The ASU also requires all annual disclosures currently required by Topic 280 to be included in interim periods. The update is effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted and requires retrospective application to all prior periods presented in the financial statements. The Company is currently assessing the timing and impact of adopting the updated provisions.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The amendments are effective for the Company’s annual periods beginning June 1, 2025, with early adoption permitted, and should be applied either prospectively or retrospectively. The Company is currently evaluating the ASU to determine its impact on the Company’s disclosures.

Stock-Based Compensation and Other Incentive Plans

12 Months Ended

Dec. 31, 2023

Stock-Based Compensation and Other Incentive Plans

Stock-Based Compensation And Other Incentive Plans

15. Stock-Based Compensation and Other Incentive Plans

Under the Company’s 2016 Omnibus Incentive Plan (the “Incentive Plan”), 3.0 million shares of the Company’s common stock were reserved for awards to officers and other selected key management employees of the Company. The Incentive Plan provides the Board of Directors with the flexibility to grant stock options, stock appreciation rights, restricted stock awards, restricted stock units, performance stock or units, phantom stock awards and rights to acquire stock through purchase under a stock purchase program (“Awards”). Awards the Board of Directors elects to pay out in cash do not impact the shares authorized in the Incentive Plan. Shares available for award under the plan were 1.5 million at December 31, 2023.

Restricted Stock Unit Awards

The Company may issue restricted stock and restricted stock units, which require no payment from the employee. Restricted stock cliff-vests at various dates and restricted stock units either vest ratably over or vest at the end of the award’s stated vesting period. Compensation expense is based on the fair value on the grant date and is recorded ratably over the vesting period utilizing the straight-line recognition method. Upon vesting, the employee receives cash compensation equal to the amount of dividends that would have been paid on the underlying shares.

During 2023, the Company granted both time and performance-based awards. The time-based awards vest ratably over a three-year period whereas the performance-based awards vest at the end of three years. The time-based awards’ grant date fair value was determined based on the stock price at the date of grant. The performance-based awards’ grant date fair value was determined using a Black-Scholes Monte Carlo simulation. An historical volatility of 67% was selected for the performance-based award based on comparator companies, and the three-year risk-free rate was derived

from yields on U.S. Government bonds. Information regarding the restricted stock units activity and weighted average grant-date fair value follows:


	Time Based Awards			Performance Based Awards
		Weighted			Weighted
		Average			Average
	Restricted	Grant-Date		Restricted	Grant-Date
	Stock Units	Fair Value		Stock Units	Fair Value
(Shares in thousands)
Outstanding at January 1, 2023	359	$	74.14	407	$	74.68
Granted & Reinvested	57		136.55	221		95.83
Forfeited/Canceled	(1)		98.82	(1)		145.11
Vested	(186)		70.56	(324)		48.45
Unvested outstanding at December 31, 2023	229	$	92.41	303	$	117.85

The Company recognized expense related to restricted stock units of $25.4 million, $27.4 million and $20.5 million for the years ended December 31, 2023, 2022 and 2021, respectively. As of December 31, 2023, there was $24.5 million of unrecognized share-based compensation expense which is expected to be recognized over a weighted-average period of approximately two years.

Workers Compensation Expense - Worker's compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accrued Workers' Compensation [Line Items]
Service cost	$ 3,974	$ 5,991	$ 7,796
Interest cost	$ 6,041	$ 4,610	$ 4,439
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Nonoperating Income (Expense)	Nonoperating Income (Expense)	Nonoperating Income (Expense)
Net amortization	$ (965)	$ 628	$ 2,363
Total workers' compensation expense
Accrued Workers' Compensation [Line Items]
Total workers' compensation expense	9,327	7,446	18,523
Occupational disease
Accrued Workers' Compensation [Line Items]
Service cost	3,974	5,991
Interest cost	6,041	4,610
Net benefit credit	9,050	11,229	14,598
Traumatic injury claims and assessments
Accrued Workers' Compensation [Line Items]
Traumatic injury claims and assessments	$ 277	$ (3,783)	$ 3,925

Insider Trading Arrangements - shares	3 Months Ended
Insider Trading Arrangements - shares	Dec. 31, 2023	Sep. 30, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Rule 10b5-1 Arrangement Modified	false
Non-Rule 10b5-1 Arrangement Modified	false
John W Lorson
Trading Arrangements, by Individual
Name		John W. Lorson.
Title		Vice President and Chief Accounting Officer
Aggregate Available		2,715

Subsequent Event (Details) - USD ($) $ / shares in Units, $ in Millions	Feb. 08, 2024	Feb. 15, 2024	Nov. 30, 2020
Subsequent Event [Line Items]
Term loan, face value			$ 155.3
Subsequent Event
Subsequent Event [Line Items]
Quarterly dividend		$ 1.65
Fixed dividend		0.25
Variable dividend		$ 1.40
Subsequent Event \| Secured Debt
Subsequent Event [Line Items]
Term loan repaid	$ 3.5
Subsequent Event \| New senior secured term loan \| Secured Debt
Subsequent Event [Line Items]
Term loan, face value	20.0
Amortization payments	$ 3.3

Accumulated Other Comprehensive Income (Loss) - Schedule of reclassifications (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss)
Interest expense	$ (14,821)	$ (20,461)	$ (23,972)
Net loss resulting from early retirement of debt	1,126	14,420
Interest and investment income	17,259	7,299	628
Total before tax	551,552	1,078,988	339,447
Provision for (benefit from) income taxes	87,514	(251,926)	1,874
Net Income (Loss)	464,038	1,330,914	$ 337,573
Pension, postretirement and other post-employment benefits
Accumulated Other Comprehensive Income (Loss)
Provision for (benefit from) income taxes	1,662	(12,548)
Available-for-sale securities
Accumulated Other Comprehensive Income (Loss)
Provision for (benefit from) income taxes	16	(35)
Reclassification out of Accumulated Other Comprehensive Income \| Derivative instruments
Accumulated Other Comprehensive Income (Loss)
Interest expense	0	(112)
Net loss resulting from early retirement of debt	0	(1,428)
Provision for (benefit from) income taxes	0	0
Net Income (Loss)	0	(1,540)
Reclassification out of Accumulated Other Comprehensive Income \| Pension, postretirement and other post-employment benefits
Accumulated Other Comprehensive Income (Loss)
Amortization of actuarial gains (losses), net	(11,208)	(2,193)
Amortization of prior service credits	98	147
Pension settlement	4,552	771
Total before tax	15,858	3,111
Provision for (benefit from) income taxes	1,662	674
Net Income (Loss)	14,196	2,437
Reclassification out of Accumulated Other Comprehensive Income \| Available-for-sale securities
Accumulated Other Comprehensive Income (Loss)
Interest and investment income	(30)	(182)
Provision for (benefit from) income taxes	(16)	(39)
Net Income (Loss)	$ (14)	$ (143)

Accrued Expenses and Other Current Liabilities (Tables)

12 Months Ended

Dec. 31, 2023

Accrued Expenses and Other Current Liabilities.

Schedule of Accrued Expenses and Other Current Liabilities


	December 31,		December 31,
	2023		2022

	(In thousands)
Payroll and employee benefits	$	37,259	$	61,836
Taxes other than income taxes		51,155		53,105
Interest		2,395		2,511
Workers’ compensation		18,724		17,584
Asset retirement obligations		6,089		8,632
Other		11,995		13,375
	$	127,617	$	157,043

Derivatives - Disclosure of fair Value of derivatives (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Derivative Assets	$ 998	$ 2,707
Derivative Liabilities	(165)
Effect of counterparty netting in derivative liabilities	0
Derivative Asset	$ 998	$ 2,707
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Derivative Liability	$ (165)
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Accrued Liabilities, Current	Accrued Liabilities, Current
Net derivatives as classified in the balance sheets	$ 833	$ 2,707
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets	998	2,707
Derivative Liabilities	(165)
Coal \| Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets		1,407
Derivative Liabilities	(165)
Heating oil - diesel purchases \| Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets	998	$ 1,300
Derivative Liabilities	$ 0

Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Consolidated Balance Sheets
Trade accounts receivable, allowance	$ 0	$ 0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	300,000	300,000
Common stock, shares issued (in shares)	30,557	28,761
Treasury stock, shares (in shares)	12,197	11,207

Employee Benefit Plans (Schedule of Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	5.20%	4.47%	2.50%
Expected return on plan assets	4.20%	4.06%	4.30%
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	5.19%	2.63%	2.17%

Risk Concentrations (Narrative) (Details) $ in Thousands, T in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) T	Dec. 31, 2022 USD ($)
Concentration Risk [Line Items]
Trade accounts receivable	$ 273,522	$ 236,999
Tons of coal sold \| T	75.0
Percentage of tons sold under long term contract	75.00%
Long term contracts percentage of company revenue	46.00%
Long-term contracts, life term, minimum	1 year
Long-term contracts, life term, maximum	4 years
Electric utilities
Concentration Risk [Line Items]
Receivables	$ 67,200	$ 94,100
Percentage of total trade accounts receivable	25.00%	40.00%
Domestic and foreign steel producers
Concentration Risk [Line Items]
Trade accounts receivable	$ 206,300	$ 142,900
Trade receivables, percentage	75.00%	60.00%

Subsequent Event

12 Months Ended

Dec. 31, 2023

Subsequent Event.

Subsequent Event

24. Subsequent Events

On February 15, 2024, the Company announced that its board of directors had approved a dividend of $1.65 per share for stockholders of record on February 29, 2024, with payment date of March 15, 2024. The dividend consists of a fixed component of $0.25 per share and a variable component of $1.40 per share.

On February 8, 2024, the Company entered into a new senior secured term loan credit agreement in the principal amount of $20.0 million. The new term loan requires quarterly principal amortization payments of $3.3 million and matures on June 30, 2025. The loan is guaranteed by substantially all of the domestic subsidiaries of the Company. Additionally, the loan is secured by substantially all of the assets of the Company and the guarantors, subject to customary exceptions (including an exclusion for owned and leased real property). The proceeds from the new term loan were used to pay off the $3.5 million balance of the existing term loan debt facility.

Leases (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Leases (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 12.8	$ 10.4	$ 8.1
Royalty expense	177.1	$ 189.7	$ 127.8
Surety bonds, lease obligations	$ 40.4
Minimum
Lessee, Lease, Description [Line Items]
Operating lease, remaining lease terms	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating lease, remaining lease terms	3 years

Debt and Financing Arrangements (Tables)

12 Months Ended

Dec. 31, 2023

Debt and Financing Arrangements

Schedule of Long-term debt


	December 31,		December 31,
	2023		2022

	(In thousands)
Term loan due 2024 ($3.5 million face value)	$	3,502	$	6,502
Tax Exempt Bonds ($98.1 million face value)		98,075		98,075
Convertible Debt		—		13,156
Other		40,529		59,472
Debt issuance costs		(1,511)		(2,929)
		140,595		174,276
Less: current maturities of debt		35,343		57,988
Long-term debt	$	105,252	$	116,288

Schedule of Maturities of Long-term Debt


Year	(In thousands)
2024	$	36,268
2025		105,838
2026		—
2027		—
2028		—
Thereafter		—
	$	142,106

Employee Benefit Plans (Schedule of Defined Benefit Plans Disclosures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	$ 3,974	$ 5,991	$ 7,796
Interest cost	6,041	4,610	4,439
Pension Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligations at beginning of year	122,430	169,976
Service cost	0	0	0
Interest cost	4,108	5,264	4,334
Settlement gain	(1,586)	(771)
Plan Settlements	(124,382)	0
Benefits paid	(4,652)	(22,164)
Other-primarily actuarial gain	5,070	(29,875)
Benefit Obligations at end of year	988	122,430	169,976
CHANGE IN PLAN ASSETS
Value of Plan Assets at beginning of year	121,127	177,499
Actual return on plan assets	4,625	(34,325)
Employer contributions	3,282	117
Plan Settlements	(124,382)	0
Benefits paid	(4,652)	(22,164)
Value of Plan Assets at end of year	0	121,127	177,499
Accrued benefit net obligation	(988)	(1,303)
ITEMS NOT YET RECOGNIZED AS A COMPONENT OF NET PERIODIC BENEFIT COST
Prior service credit	0	945
Accumulated gain	1,150	5,164
Total not yet recognized as a component of net periodic benefit cost	1,150	6,109
BALANCE SHEET AMOUNTS
Noncurrent asset	0	0
Current liability	(110)	(202)
Noncurrent liability	(878)	(1,101)
Total balance sheet amounts	(988)	(1,303)
Other Postretirement Benefits
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligations at beginning of year	54,514	79,245
Service cost	231	282	341
Interest cost	2,694	2,006	2,113
Settlement gain	0	0
Plan Settlements	0	0
Benefits paid	(3,858)	(4,834)
Other-primarily actuarial gain	(2,227)	(22,185)
Benefit Obligations at end of year	51,354	54,514	79,245
CHANGE IN PLAN ASSETS
Value of Plan Assets at beginning of year	0	0
Actual return on plan assets	0	0
Employer contributions	3,858	4,834
Plan Settlements	0	0
Benefits paid	(3,858)	(4,834)
Value of Plan Assets at end of year	0	0	$ 0
Accrued benefit net obligation	(51,354)	(54,514)
ITEMS NOT YET RECOGNIZED AS A COMPONENT OF NET PERIODIC BENEFIT COST
Prior service credit	0	0
Accumulated gain	32,871	40,334
Total not yet recognized as a component of net periodic benefit cost	32,871	40,334
BALANCE SHEET AMOUNTS
Noncurrent asset	0	0
Current liability	(3,860)	(4,840)
Noncurrent liability	(47,494)	(49,674)
Total balance sheet amounts	$ (51,354)	$ (54,514)

Fair Value Measurements - Financial assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets:
Investments in marketable securities	$ 32,724	$ 36,993
Derivatives	998	3,955
Fund for asset retirement obligations	142,266	135,993
Total assets	175,988	176,941
Liabilities:
Derivatives	165
Level 1
Assets:
Investments in marketable securities	28,773	28,301
Derivatives		0
Fund for asset retirement obligations	142,266	135,993
Total assets	171,039	164,294
Liabilities:
Derivatives		0
Level 2
Assets:
Investments in marketable securities	3,951	8,692
Derivatives		2,655
Total assets	3,951	11,347
Liabilities:
Derivatives	165
Level 3
Assets:
Investments in marketable securities	0	0
Derivatives	998	1,300
Fund for asset retirement obligations	0	0
Total assets	998	1,300
Liabilities:
Derivatives	$ 0	$ 0

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net Income (Loss)	$ 464,038	$ 1,330,914	$ 337,573

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Earnings per Common Share (Tables)

12 Months Ended

Dec. 31, 2023

Earnings per Common Share

Schedule of Weighted Average Number of Shares


	Year Ended	Year Ended	Year Ended
	December 31,	December 31,	December 31,
	2023	2022	2021
(In Thousands)
Net income attributable to common shares	$ 464,038	$ 1,330,914	$ 337,573
Adjustment of interest expense attributable to convertible notes	108	4,726	-
Adjustment for inducement payments	-	4,914	-
Diluted net income attributable to common shareholders	$ 464,146	$ 1,340,554	$ 337,573


Weighted average shares outstanding:
Basic weighted average shares outstanding	18,233	17,136	15,318
Effect of dilutive securities	866	1,730	654
Convertible Notes	84	2,119	1,607
Diluted weighted average shares outstanding	19,183	20,985	17,579

Revenue Recognition - Schedule of revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Revenues	$ 3,145,843	$ 3,724,593	$ 2,208,042
North America revenues
Disaggregation of Revenue [Line Items]
Revenues	1,372,316	1,413,141	1,059,003
Seaborne revenues
Disaggregation of Revenue [Line Items]
Revenues	1,773,527	2,311,452	1,149,039
Operating Segments \| MET
Disaggregation of Revenue [Line Items]
Revenues	1,892,326	2,157,710	1,149,133
Operating Segments \| MET \| North America revenues
Disaggregation of Revenue [Line Items]
Revenues	342,070	232,831	163,833
Operating Segments \| MET \| Seaborne revenues
Disaggregation of Revenue [Line Items]
Revenues	1,550,256	1,924,879	985,300
Operating Segments \| Thermal
Disaggregation of Revenue [Line Items]
Revenues	1,253,517	1,566,883	1,057,480
Operating Segments \| Thermal \| North America revenues
Disaggregation of Revenue [Line Items]
Revenues	1,030,246	1,180,310	893,741
Operating Segments \| Thermal \| Seaborne revenues
Disaggregation of Revenue [Line Items]
Revenues	223,271	386,573	163,739
Corporate, Other and Eliminations
Disaggregation of Revenue [Line Items]
Revenues	0	0	1,429
Corporate, Other and Eliminations \| North America revenues
Disaggregation of Revenue [Line Items]
Revenues	0	0	1,429
Corporate, Other and Eliminations \| Seaborne revenues
Disaggregation of Revenue [Line Items]
Revenues	$ 0	$ 0	$ 0

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

- Definition

+ References

+ Details

Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Taxes
Income tax provision at statutory rate	$ 115,826	$ 226,587	$ 71,284
Percentage depletion and other permanent items	(30,585)	(52,647)	(29,392)
State taxes, net of effect of federal taxes	2,725	2,988	16,490
Change in valuation allowance	(879)	(420,688)	(69,603)
Other, net	427	(8,166)	13,095
Provision for (benefit from) income taxes	$ 87,514	$ (251,926)	$ 1,874

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Consolidated Statements of Stockholders' Equity(Parenthetical) - shares	12 Months Ended			57 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023
Consolidated Statements of Stockholders' Equity
Purchase of shares of common stock under share repurchase program	989,792	1,118,457		12,196,627
Issuance of shares of common stock under long-term incentive plan (in shares)	311,506	92,314	157,609
Issuance of shares of common stock for convertible debt exchanged (in shares)		2,636,660
Issuance of shares of common stock for warrants exercised (in shares)	1,484,226	561,561		1,484,226

Accumulated Other Comprehensive Income (Loss) - Schedule of accumulated other comprehensive income (loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	$ 1,365,580	$ 683,866	$ 283,561
Tax effect	87,514	(251,926)	1,874
Ending Balance	1,479,456	1,365,580	683,866
Accumulated Other Comprehensive Income (loss)
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	61,429	14,158	(35,701)
Unrealized (losses) gains	(8,497)	61,243
Amounts reclassified from accumulated other comprehensive income (loss)	(15,828)	(1,389)
Tax effect	1,678	(12,583)
Ending Balance	38,782	61,429	14,158
Derivative Instruments
Accumulated Other Comprehensive Income (Loss)
Beginning Balance		(1,763)
Unrealized (losses) gains		223
Amounts reclassified from accumulated other comprehensive income (loss)		1,540
Ending Balance			(1,763)
Pension, Postretirement and Other Post-Employment Benefits
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	61,485	16,103
Unrealized (losses) gains	(8,506)	61,041
Amounts reclassified from accumulated other comprehensive income (loss)	(15,858)	(3,111)
Tax effect	1,662	(12,548)
Ending Balance	38,783	61,485	16,103
Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss)
Beginning Balance	(56)	(182)
Unrealized (losses) gains	9	(21)
Amounts reclassified from accumulated other comprehensive income (loss)	30	182
Tax effect	16	(35)
Ending Balance	$ (1)	$ (56)	$ (182)

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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-Topic 825
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-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
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-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

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-Paragraph 2
-Subparagraph (SAB Topic 4.E)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480418/310-10-S99-2

+ Details

Debt and Financing Arrangements

12 Months Ended

Dec. 31, 2023

Debt and Financing Arrangements

Debt and Financing Arrangements

10. Debt and Financing Arrangements


	December 31,		December 31,
	2023		2022

	(In thousands)
Term loan due 2024 ($3.5 million face value)	$	3,502	$	6,502
Tax Exempt Bonds ($98.1 million face value)		98,075		98,075
Convertible Debt		—		13,156
Other		40,529		59,472
Debt issuance costs		(1,511)		(2,929)
		140,595		174,276
Less: current maturities of debt		35,343		57,988
Long-term debt	$	105,252	$	116,288

Term Loan Facility

In 2017, the Company entered into a senior secured term loan credit agreement in an aggregate principal amount of $300 million (the “Term Loan Debt Facility”) with Credit Suisse AG, Cayman Islands Branch, as administrative agent and collateral agent, and the other financial institutions from time to time party thereto (collectively, the “Lenders”). The Term Loan Debt Facility was issued at 99.50% of the face amount and will mature on March 7, 2024. The term loans provided under the Term Loan Debt Facility (the “Term Loans”) are subject to quarterly principal amortization payments in an amount equal to $0.8 million. The interest rate on the Term Loan Debt Facility is, at the option of Arch Resources, either (i) LIBOR plus an applicable margin of 2.75%, subject to a 1.00% LIBOR floor, or (ii) a base rate plus an applicable margin of 1.75%.

The Term Loan Debt Facility is guaranteed by all existing and future wholly owned domestic subsidiaries of the Company (collectively, the “Subsidiary Guarantors” and, together with Arch Resources, the “Loan Parties”), subject to customary exceptions, and is secured by first priority security interests on substantially all assets of the Loan Parties, including 100% of the voting equity interests of directly owned domestic subsidiaries and 65% of the voting equity interests of directly owned foreign subsidiaries, subject to customary exceptions.

The Company has the right to prepay Term Loans at any time and from time to time in whole or in part without premium or penalty, upon written notice, except that any prepayment of Term Loans that bear interest at the LIBOR Rate other than at the end of the applicable interest periods therefor shall be made with reimbursement for any funding losses and redeployment costs of the Lenders resulting therefrom.

The Term Loan Debt Facility is subject to certain usual and customary mandatory prepayment events, including 100% of net cash proceeds of (i) debt issuances (other than debt permitted to be incurred under the terms of the New Term Loan Debt Facility) and (ii) non-ordinary course asset sales or dispositions, subject to customary thresholds, exceptions and reinvestment rights.

The Term Loan Debt Facility contains customary affirmative covenants and representations.

The Term Loan Debt Facility also contains customary negative covenants, which, among other things, and subject to certain exceptions, include restrictions on (i) indebtedness, (ii) liens, (iii) liquidations, mergers, consolidations and acquisitions, (iv) disposition of assets or subsidiaries, (v) affiliate transactions, (vi) creation or ownership of certain subsidiaries, partnerships and joint ventures, (vii) continuation of or change in business, (viii) restricted payments, (ix) prepayment of subordinated and junior lien indebtedness, (x) restrictions in agreements on dividends, intercompany loans and granting liens on the collateral, (xi) loans and investments, (xii) sale and leaseback transactions, (xiii) changes in organizational documents and fiscal year and (xiv) transactions with respect to bonding subsidiaries. The Term Loan Debt Facility does not contain any financial maintenance covenant.

The Term Loan Debt Facility contains customary events of default, subject to customary thresholds and exceptions, including, among other things, (i) nonpayment of principal and nonpayment of interest and fees, (ii) a material inaccuracy of a representation or warranty at the time made, (iii) a failure to comply with any covenant, subject to customary grace periods in the case of certain affirmative covenants, (iv) cross-events of default to indebtedness of at least $50 million, (v) cross-events of default to surety, reclamation or similar bonds securing obligations with an aggregate face amount of at least $50 million, (vi) uninsured judgments in excess of $50 million, (vii) any loan document shall cease to be a legal, valid and binding agreement, (viii) uninsured losses or proceedings against assets with a value in excess of $50 million, (ix) certain ERISA events, (x) a change of control or (xi) bankruptcy or insolvency proceedings relating to the Company or any material subsidiary of the Company.

During the year ended December 31, 2022, the Company repaid $273.8 million of the Term Loan leaving a remaining balance of $6.5 million. The remaining balance of $6.5 million was left as certain terms and conditions governing the Term Loan are incorporated into the Company’s outstanding indebtedness. As a result of the repayment, the Company recorded $4.1 million in “net loss resulting from early retirement of debt” during the year ended December 31, 2022 in the accompanying Consolidated Income Statements relating to deferred financing fees, original issue

discount, and the ineffective portion of an interest rate swap designated as a cashflow hedge, partially offset by gains on repurchases of the Term Loans.

Accounts Receivable Securitization Facility

On August 3, 2022, the Company amended and extended its existing trade accounts receivable securitization facility provided to Arch Receivable Company, LLC, a special-purpose entity that is a wholly owned subsidiary of Arch Resources (“Arch Receivable”) (the “Securitization Facility”), which supports the issuance of letters of credit and requests for cash advances. The amendment to the Securitization Facility increased the size of the facility from $110 million to $150 million of borrowing capacity and extended the maturity date to August 1, 2025.

Under the Securitization Facility, Arch Receivable, Arch Resources and certain of Arch Resources’ subsidiaries party to the Securitization Facility have granted to the administrator of the Securitization Facility a first priority security interest in eligible trade accounts receivable generated by such parties from the sale of coal and all proceeds thereof. As of December 31, 2023, letters of credit totaling $50.2 million were outstanding under the facility with $99.8 million available for borrowings.

Inventory-Based Revolving Credit Facility

On August 3, 2022, Arch Resources amended the senior secured inventory-based revolving credit facility in an aggregate principal amount of $50 million (the “Inventory Facility”) with Regions Bank (“Regions”) as administrative agent and collateral agent, as lender and swingline lender and as letter of credit issuer. Availability under the Inventory Facility is subject to a borrowing base consisting of (i) 85% of the net orderly liquidation value of eligible coal inventory, plus (ii) the lesser of (x) 85% of the net orderly liquidation value of eligible parts and supplies inventory and (y) 35% of the amount determined pursuant to clause (i), plus (iii) 100% of Arch Resources’ Eligible Cash (defined in the Inventory Facility), subject to reduction for reserves imposed by Regions. The amendment of the Inventory Facility extended the maturity of the facility to August 3, 2025.

Revolving loan borrowings under the Inventory Facility bear interest at a per annum rate equal to, at the option of Arch Resources, either the base rate or the Term Secured Overnight Financing Rate (“SOFR”) plus, in each case, a margin ranging from 2.25% to 3.50% (in the case of Term SOFR loans) subject to a 0.75% floor, and 1.25% to 2.50% (in the case of base rate loans) determined using a Liquidity-based grid. Letters of credit under the Inventory Facility are subject to a fee in an amount equal to the applicable margin for Term SOFR loans, plus customary fronting and issuance fees.

All existing and future direct and indirect domestic subsidiaries of Arch Resources, subject to customary exceptions, will either constitute co-borrowers under or guarantors of the Inventory Facility (collectively with Arch Resources, the “Loan Parties”). The Inventory Facility is secured by first priority security interests in the ABL Priority Collateral (defined in the Inventory Facility) of the Loan Parties and second priority security interests in substantially all other assets of the Loan Parties, subject to customary exceptions (including an exception for the collateral that secures the Securitization Facility).

Arch Resources has the right to prepay borrowings under the Inventory Facility at any time and from time to time in whole or in part without premium or penalty, upon written notice, except that any prepayment of such borrowings that bear interest at the Term SOFR rate other than at the end of the applicable interest periods therefore shall be made with reimbursement for any funding losses and redeployment costs of the Lender resulting therefrom.

The Inventory Facility is subject to certain usual and customary mandatory prepayment events, including non-ordinary course asset sales or dispositions, subject to customary thresholds, exceptions (including exceptions for required prepayments under Arch Resources’ term loan facility) and reinvestment rights.

The Inventory Facility contains certain customary affirmative and negative covenants; events of default, subject to customary thresholds and exceptions; and representations, including certain cash management and reporting requirements that are customary for asset-based credit facilities. The Inventory Facility also includes a requirement to maintain Liquidity equal to or exceeding $100 million at all times. As of December 31, 2023, letters of credit totaling $26.2 million were outstanding under the facility with $23.8 million available for borrowings.

Equipment Financing

On March 4, 2020, the Company entered into an equipment financing arrangement accounted for as debt. The Company received $53.6 million in exchange for conveying an interest in certain equipment in operation at its Leer Mine and entered into a master lease arrangement for that equipment. The financing arrangement contains customary terms and events of default and provides for 48 monthly payments with an average interest rate of 6.34% maturing on March 4, 2024. Upon maturity, all interests in the subject equipment will revert back to the Company.

On July 29, 2021, the Company entered into an additional equipment financing arrangement accounted for as debt. The Company received $23.5 million in exchange for conveying an interest in certain equipment in operation at its Powder River Basin operations and entered into a master lease arrangement for that equipment. The financing arrangement contains customary terms and events of default and provides for 42 monthly payments with an average implied interest rate of 7.35% maturing on February 1, 2025. Upon maturity, the Company will have the option to purchase the equipment.

Tax Exempt Bonds

On July 2, 2020, the West Virginia Economic Development Authority (the “Issuer”) issued $53.1 million aggregate principal amount of Solid Waste Disposal Facility Revenue Bonds (Arch Resources Project), Series 2020 (the “2020 Tax Exempt Bonds”) pursuant to an Indenture of Trust dated as of June 1, 2020 (as amended to date, the “Indenture of Trust”) between the Issuer and Citibank, N.A., as trustee (the “Trustee”). On March 4, 2021, the Issuer issued an additional $45.0 million of Series 2021 Tax Exempt Bonds (the “2021 Tax Exempt Bonds” and together with the 2020 Tax Exempt Bonds, the “Tax Exempt Bonds”). The proceeds of the Tax Exempt Bonds were loaned to the Company pursuant to a Loan Agreement dated as of June 1, as supplemented by a First Amendment to Loan Agreement dated as of March 1, 2021 (collectively, the “Loan Agreement”), each between the Issuer and the Company. The Tax Exempt Bonds are payable solely from payments to be made by the Company under the Loan Agreement as evidenced by a Note from the Company to the Trustee. The proceeds of the Tax Exempt Bonds were used to finance certain costs of the acquisition, construction, reconstruction, and equipping of solid waste disposal facilities at the Company’s Leer South development, and for capitalized interest and certain costs related to issuance of the Tax Exempt Bonds.

The Tax Exempt Bonds bear interest payable each January 1 and July 1, and have a final maturity of July 1, 2045; however, the Tax Exempt Bonds are subject to mandatory tender on July 1, 2025 at a purchase price equal to 100% of the principal amount of the Tax Exempt Bonds, plus accrued interest to July 1, 2025. The 2020 Tax Exempt Bonds and 2021 Tax Exempt Bonds bear interest of 5% and 4.125%, respectively.

The Tax Exempt Bonds are subject to redemption (i) in whole or in part at any time on or after January 1, 2025 at the option of the Issuer, upon the Company’s direction at a redemption price of par, plus interest accrued to the redemption date; and (ii) at par plus interest accrued to the redemption date from certain excess Tax Exempt Bonds proceeds as further described in the Indenture of Trust.

The Company’s obligations under the Loan Agreement are (i) except as otherwise described below, secured by first priority liens on and security interests in substantially all of the Company’s and Subsidiary Guarantors’ real property and other assets, subject to certain customary exceptions and permitted liens, and in any event excluding accounts receivable and inventory; and (ii) jointly and severally guaranteed by the Subsidiary Guarantors, subject to customary exceptions.

The collateral securing the Company’s obligations under the Loan Agreement is substantially the same as the collateral securing the obligations under the Term Loan Debt Facility other than with respect to variances in certain real property collateral. The real property securing the Company’s obligations under the Loan Agreement includes a subset of the real property collateral securing the obligations under the Term Loan Debt Facility and includes only mortgages on substantially all of the Company’s revenue generating real property and assets.

The Loan Agreement contains certain affirmative covenants and representations, including but not limited to: (i) maintenance of a rating on the Tax Exempt Bonds; (ii) maintenance of proper books of records and accounts; (iii) agreement to add additional guarantors to guarantee the obligations under the Loan Agreement in certain circumstances; (iv) procurement of customary insurance; and (v) preservation of legal existence and certain rights, franchises, licenses and permits. The Loan Agreement also contains certain customary negative covenants, which, among other things, and subject to certain exceptions, include restrictions on (i) release of collateral securing the Company’s obligations under the Loan Agreement; (ii) mergers and consolidations and disposition of assets, and (iii) restrictions on actions that may jeopardize the tax-exempt status of the Tax Exempt Bonds.

The Loan Agreement contains customary events of default, subject to customary thresholds and exceptions, including, among other things: (i) nonpayment of principal, purchase price, interest and other fees (subject to certain cure periods); (ii) bankruptcy or insolvency proceedings relating to us; (iii) material inaccuracy of a representation or warranty at the time made; (iv) cross-events of default to indebtedness of at least $50 million; and (v) cross defaults to the Indenture of Trust, the guaranty related to the Tax Exempt Bonds or any related security documents.

Convertible Debt

On November 3, 2020, the Company issued $155.3 million in aggregate principal amount of 5.25% convertible senior notes due 2025 (“Convertible Notes” or “Convertible Debt”). The net proceeds from the issuance of the Convertible Notes, after deducting offering related costs of $5.1 million and cost of a “Capped Call Transaction” as defined below of $17.5 million, were approximately $132.7 million.

During the year ended December 31, 2022, the Company entered into exchange and repurchase agreements for $142.1 million principal amount of the Convertible Notes for aggregate consideration consisting of $208.1 million in cash and approximately 2.6 million shares of Arch Resources common stock. In connection with the exchanges and repurchases, the Company recognized a total loss of $10.3 million which includes inducement premium payments of $5.0 million, unamortized deferred financing fees of $3.8 million and professional fees of $1.5 million. This amount is included as “Net loss resulting from early retirement of debt” in the accompanying Consolidated Income Statements.

During the first half of 2023, the Company repurchased the remaining Convertible Notes with a principal amount of $13.2 million for aggregate consideration consisting of $58.4 million in cash. In connection with the repurchase, the Company recognized a loss of $1.1 million. This amount is included as “Net loss resulting from early retirement of debt” in the accompanying Consolidated Income Statements.

Total interest expense related to the Convertible Debt for the year ended December 31, 2023 was less than $0.1 million and December 31, 2022 was $4.7 million, which was related to the contractual interest coupon of $4.1 million and $0.6 million of amortization of deferred financing fees.

Capped Call Transactions

In connection with the offering of the Convertible Notes, the Company entered into privately negotiated convertible note hedge transactions (collectively, the “Capped Call Transactions”). The Capped Call Transactions cover, subject to customary anti-dilution adjustments, the number of shares of the Company’s common stock that initially underlie the Convertible Notes.

The Capped Call Transactions are expected generally to reduce the potential dilution and/or offset any cash payments the Company is required to make in excess of the principal amount due upon conversion of the Convertible Notes in the event that the market price of the Company’s common stock is greater than the strike price of the Capped Call Transactions, which was initially $37.325 per share and the initial cap price was $52.255 per share. The initial call and cap prices are subject to adjustments under the terms of the underlying capped call agreements, including for various transactions such as the payment of dividends. The number of shares underlying the Capped Call Transactions at inception was 4.2 million.

The cap price of the Capped Call Transactions was initially $52.2550 per share, which represented a premium of 75% over the last reported sale price of the Company’s common stock on October 29, 2020. The cost of the Capped Call Transactions was approximately $17.5 million with a maturity date of November 15, 2025.

As of December 31, 2023, the Capped Call Transactions remain outstanding and have an intrinsic value of $62.1 million. If the Company were to be unwind the capped call, it could be done in either shares or cash.

The Capped Call Transactions are separate transactions, in each case entered into between the Company and the respective Option Counterparty, and were not part of the terms of the Convertible Notes. Holders of the Convertible Notes do not have any rights with respect to the Capped Call Transactions. Additionally, the cost of the Capped Call Transactions is not expected to be tax deductible as the Company did not elect to integrate the Capped Call Transactions into the notes for tax purposes. As the Capped Call Transactions meet certain accounting criteria, they were classified as equity and are not accounted for as derivatives.

Debt Maturities

The contractual maturities of debt as of December 31, 2023 are as follows:


Year	(In thousands)
2024	$	36,268
2025		105,838
2026		—
2027		—
2028		—
Thereafter		—
	$	142,106

Financing Costs

The Company paid financing costs of $0.0 million, $1.0 million and $2.1 million during the years ended December 31, 2023, 2022 and 2021, respectively.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//470/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 287,807	$ 236,059
Short-term investments	32,724	36,993
Restricted cash	1,100	1,100
Trade accounts receivable (net of $0 allowance at December 31, 2023 and December 31, 2022)	273,522	236,999
Other receivables	13,700	18,301
Inventories	244,261	223,015
Other current assets	64,653	71,384
Total current assets	917,767	823,851
Property, plant and equipment, net
Coal lands and mineral rights	402,387	406,085
Plant and equipment	1,099,511	968,420
Deferred mine development	509,637	475,037
Property, plant and equipment, gross	2,011,535	1,849,542
Less accumulated depreciation, depletion and amortization	(782,644)	(662,514)
Property, plant and equipment, net	1,228,891	1,187,028
Other assets
Deferred income taxes	124,024	209,470
Equity investments	22,815	17,267
Fund for asset retirement obligations	142,266	135,993
Other noncurrent assets	48,410	59,499
Total other assets	337,515	422,229
Total assets	2,484,173	2,433,108
Current Liabilities
Accounts payable	205,001	211,848
Accrued expenses and other current liabilities	127,617	157,043
Current maturities of debt	35,343	57,988
Total current liabilities	367,961	426,879
Long-term debt	105,252	116,288
Asset retirement obligations	255,740	235,736
Accrued pension benefits	878	1,101
Accrued postretirement benefits other than pension	47,494	49,674
Accrued workers' compensation	154,650	155,756
Other noncurrent liabilities	72,742	82,094
Total liabilities	1,004,717	1,067,528
Stockholders' equity
Common stock, $0.01 par value, authorized 300,000 shares, issued 30,557 and 28,761 shares at December 31, 2023 and December 31, 2022, respectively	306	288
Paid-in capital	720,029	724,660
Retained earnings	1,830,018	1,565,374
Treasury stock, 12,197 and 11,207 shares at December 31, 2023 and December 31, 2022, respectively, at cost	(1,109,679)	(986,171)
Accumulated other comprehensive income	38,782	61,429
Total stockholders' equity	1,479,456	1,365,580
Total liabilities and stockholders' equity	$ 2,484,173	$ 2,433,108

Inventories (Tables)

12 Months Ended

Dec. 31, 2023

Inventories

Inventories


	December 31,		December 31,
	2023		2022

	(In thousands)
Coal	$	99,174	$	96,954
Repair parts and supplies		145,087		126,061
	$	244,261	$	223,015

Investments in Available-for-Sale Securities

12 Months Ended

Dec. 31, 2023

Investments in Available-for-Sale Securities

Investments in Available-for-Sale Securities

6. Investments in Available-for-Sale Securities

The Company has invested in marketable debt securities, primarily highly liquid U.S. Treasury securities and investment grade corporate bonds. These investments are held in the custody of a major financial institution. These securities are classified as available-for-sale securities and, accordingly, the unrealized gains and losses are recorded through other comprehensive income.

The Company’s investments in available-for-sale marketable securities are as follows:


	December 31, 2023

			Gross					Allowance
			Unrealized					for - Credit	Fair
	Cost Basis		Gains		Losses			Losses	Value

	(In thousands)
Available-for-sale:
U.S. government and agency securities	$	28,764	$	14	$	(5)	$	—	$	28,773
Corporate notes and bonds		3,951		1		(1)		—		3,951
Total Investments	$	32,715	$	15	$	(6)	$	—	$	32,724


	December 31, 2022

			Gross					Allowance
			Unrealized					for - Credit	Fair
	Cost Basis		Gains			Losses		Losses	Value

	(In thousands)
Available-for-sale:
U.S. government and agency securities	$	28,325	$	1	$	(25)	$	—	$	28,301
Corporate notes and bonds		8,689		20		(17)		—		8,692
Total Investments	$	37,014	$	21	$	(42)	$	—	$	36,993

The aggregate fair value of investments with unrealized losses that had been owned for less than a year was $2.2 million and $22.6 million at December 31, 2023 and 2022, respectively. The aggregate fair value of investments with unrealized losses that have been owned for over a year was $2.3 million and $0.0 million at December 31, 2023 and 2022, respectively.

The debt securities outstanding at December 31, 2023 have maturity dates ranging through the first quarter of 2025. The Company classifies its investments as current based on the nature of the investments and their availability to provide cash for use in current operations, if needed.

Accrued Expenses and Other Current Liabilities

12 Months Ended

Dec. 31, 2023

Accrued Expenses and Other Current Liabilities.

Accrued Expenses and Other Current Liabilities

9. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consist of the following:


	December 31,		December 31,
	2023		2022

	(In thousands)
Payroll and employee benefits	$	37,259	$	61,836
Taxes other than income taxes		51,155		53,105
Interest		2,395		2,511
Workers’ compensation		18,724		17,584
Asset retirement obligations		6,089		8,632
Other		11,995		13,375
	$	127,617	$	157,043

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies

Commitments and Contingencies

22. Commitments and Contingencies

The Company is a party to numerous claims and lawsuits with respect to various matters. As of December 31, 2023 and 2022, the Company had accrued $0.0 million and $2.0 million, respectively, for all legal matters, all classified as current. The ultimate resolution of any such legal matter could result in outcomes which may be materially different from amounts the Company has accrued for such matters. The Company believes it has recorded adequate reserves for these matters.

In the normal course of business, the Company is a party to certain financial instruments with off-balance sheet risk, such as bank letters of credit, performance or surety bonds, and other guarantees and indemnities related to the obligations of affiliated entities which are not reflected in the Company’s Consolidated Balance Sheets. However, the underlying liabilities that they secure, such as asset retirement obligations, workers’ compensation liabilities, and other obligations, are reflected in the Company’s Consolidated Balance Sheets. As of December 31, 2023, the Company had outstanding surety bonds with a face amount of $552.5 million to secure various obligations and commitments and $76.4 million of letters of credit under its Securitization and Inventory Facilities used to collateralize certain obligations. The Company had posted $5.6 million in cash collateral related to various obligations; this amount is recorded within “Other noncurrent assets” on the Consolidated Balance Sheets.

As of December 31, 2023, the Company’s reclamation-related obligations of $261.8 million were supported by surety bonds of $455.7 million; and the Company has posted $0.6 million in cash collateral related to reclamation surety bonds. This amount is recorded within “Other noncurrent assets” on the Consolidated Balance Sheets. Additionally, through December 31, 2023, the Company has contributed $142.3 million to a fund that will serve to defease the long-term asset retirement obligation for its thermal asset base; this amount is recorded as “Fund for asset retirement obligations” on the Consolidated Balance Sheets. The funds will be utilized for final mine closure reclamation activities.

The Company has unconditional purchase obligations relating to purchases of materials and supplies and capital commitments, other than reserve acquisitions, and is also a party to transportation capacity commitments. The future commitments under these agreements total $221.2 million in 2024, and is immaterial thereafter.

Fair Value Measurements (Details) - USD ($) $ in Thousands	12 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contribution to fund asset retirement obligations	$ 6,273	$ 115,993	$ 20,000
Fair value of debt, including amounts classified as current	142,100	$ 223,000
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net unrealized gains (losses) related to level 3 financial instruments	$ 2,600
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Operating Income (Expense), Net
Asset retirement obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contribution to fund asset retirement obligations	$ 142,300

Employee Benefit Plans

12 Months Ended

Dec. 31, 2023

Employee Benefit Plans

Employee Benefit Plans

17. Employee Benefit Plans

Defined Benefit Pension and Other Postretirement Benefit Plans

The Company provides funded and unfunded non-contributory defined benefit pension plans covering certain of its salaried and hourly employees. Benefits are generally based on the employee’s age and compensation. The Company funds the plans in an amount not less than the minimum statutory funding requirements or more than the maximum amount that can be deducted for U.S. federal income tax purposes.

The Company also currently provides certain postretirement medical and life insurance coverage for eligible employees. Generally, covered employees who terminate employment after meeting eligibility requirements are eligible for postretirement coverage for themselves and their dependents. The Company offers a subsidy to eligible retirees based on age and years of service at retirement and contain other cost-sharing features such as deductibles and coinsurance. The Company’s current funding policy is to fund the cost of all postretirement benefits as they are paid.

On January 1, 2015, the Company’s cash balance and excess plans were amended to freeze new service credits for any new or active employees.

In February 2022, the Board of Directors approved the termination of the Company’s Cash Balance Pension Plan. The Company has executed plan amendments regarding the termination and filed an Application for Determination for Terminating Pension Plan with the Internal Revenue Service (“IRS”), which was approved by the IRS during the first quarter of 2023. The Company also prepared and filed appropriate notices and documents related to the Pension Plan's termination and wind-down with the Pension Benefit Guaranty Corporation (“PBGC”). To complete the termination of the plan, the Company made a $3.2 million cash contribution into the plan in order to complete lump sum payments and to purchase annuity contracts for plan participants. An immaterial gain was recognized on the plan termination, which is reflected in the Consolidated Incomes Statements line item “Non-service related pension and postretirement benefits credits (costs)”. The Company no longer administers or pays the retirement benefits of the Cash Balance Pension Plan.

Obligations and Funded Status.

Summaries of the changes in the benefit obligations, plan assets and funded status of the plans are as follows:


	Pension Benefits				Other Postretirement Benefits
	Year Ended		Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,		December 31,
	2023		2022		2023		2022
(In thousands)
CHANGE IN BENEFIT OBLIGATIONS
Benefit obligations at beginning of period	$	122,430	$	169,976	$	54,514	$	79,245
Service cost		—		—		231		282
Interest cost		4,108		5,264		2,694		2,006
Settlement gain		(1,586)		(771)		—		—
Plan Settlements		(124,382)		—		—		—
Benefits paid		(4,652)		(22,164)		(3,858)		(4,834)
Other-primarily actuarial gain		5,070		(29,875)		(2,227)		(22,185)
Benefit obligations at end of period	$	988	$	122,430	$	51,354	$	54,514
CHANGE IN PLAN ASSETS
Value of plan assets at beginning of period	$	121,127	$	177,499	$	—	$	—
Actual return on plan assets		4,625		(34,325)		—		—
Employer contributions		3,282		117		3,858		4,834
Plan Settlements		(124,382)		—		—		—
Benefits paid		(4,652)		(22,164)		(3,858)		(4,834)
Value of plan assets at end of period	$	—	$	121,127	$	—	$	—
Accrued benefit net obligation	$	(988)	$	(1,303)	$	(51,354)	$	(54,514)
ITEMS NOT YET RECOGNIZED AS A COMPONENT OF NET PERIODIC BENEFIT COST
Prior service credit	$	—	$	945	$	—	$	—
Accumulated gain		1,150		5,164		32,871		40,334
	$	1,150	$	6,109		32,871	$	40,334
BALANCE SHEET AMOUNTS
Noncurrent asset	$	—	$	—	$	—	$	—
Current liability		(110)		(202)		(3,860)		(4,840)
Noncurrent liability		(878)		(1,101)		(47,494)		(49,674)
	$	(988)	$	(1,303)	$	(51,354)	$	(54,514)

Pension Benefits

The accumulated benefit obligation for all pension plans was $1.0 million and $122.4 million at December 31, 2023 and 2022, respectively. The termination of the Company’s Cash Balance Pension Plan significantly impacted the benefit obligation.

The weighted-average interest credit rate for the cash balance pension plan was 4.25% at December 31, 2022.

Other Postretirement Benefits

Significant gains and losses affecting the benefit obligations included:

●

the lower discount rate increased plan obligations by $1.0 million;

●

the claims cost assumptions were updated decreasing plan obligations by $0.9 million; and

●

updated census data resulted in a decrease of plan obligations in the amount of $1.4 million.

Components of Net Periodic Benefit Cost. The following table details the components of pension and postretirement benefit costs (credits):


	Pension Benefits						Other Postretirement Benefits
	Year Ended		Year Ended		Year Ended		Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,		December 31,		December 31,		December 31,
	2023		2022		2021		2023		2022		2021
(In thousands)
Service cost	$	—	$	—	$	—	$	231	$	282	$	341
Interest cost⁽¹⁾		4,108		5,264		4,334		2,694		2,006		2,113
Settlements/Terminations⁽¹⁾		(1,586)		(771)		(1,768)		—		—		—
Expected return on plan assets⁽¹⁾		(4,048)		(6,173)		(7,245)		—		—		—
Amortization of prior service credits⁽¹⁾		(98)		(147)		(128)		—		—		—
Amortization of other actuarial losses (gains) ⁽¹⁾		(553)		(313)		(62)		(9,690)		(2,508)		—
Net benefit cost (credit)	$	(2,177)	$	(2,140)	$	(4,869)	$	(6,765)	$	(220)	$	2,454

(1)

In accordance with the adoption of ASU 2017-07, “Compensation-Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” these costs are recorded within Nonoperating expenses in the Consolidated Income Statements on the line item “Non-service related pension and postretirement benefit credits (costs).”

The differences generated from changes in assumed discount rates and returns on plan assets are amortized into earnings over the remaining service attribution periods of the employees using the corridor method.

Assumptions. The following table provides the assumptions used to determine the actuarial present value of projected benefit obligations for the respective periods.


	Year Ended	Year Ended
	December 31,	December 31,
	2023	2022
(Percentages)
Pension Benefits
Discount rate	4.89	5.20/5.15

Other Postretirement Benefits
Discount rate	4.94	5.19

The following table provides the weighted average assumptions used to determine net periodic benefit cost for the respective periods.


	Year Ended	Year Ended	Year Ended
	December 31,	December 31,	December 31,
	2023	2022	2021
(Percentages)
Pension Benefits
Discount rate	5.20	4.47	2.50
Expected return on plan assets	4.20	4.06	4.30

Other Postretirement Benefits
Discount rate	5.19	2.63	2.17

The discount rates used in 2023, 2022 and 2021 were reevaluated during the year for settlements. The obligations are remeasured at an updated discount rate that impacts the benefit cost recognized subsequent to the remeasurement.

As of December 31, 2023, there are no pension plan assets. For December 31, 2022, the Company established the expected long-term rate of return at the beginning of each fiscal year based upon historical returns and projected returns on the underlying mix of invested assets. The Company utilized modern portfolio theory modeling techniques in the development of its return assumptions. This technique projects rates of return that can be generated through various asset allocations that lie within the risk tolerance set forth by members of the Company’s retirement committee. The risk assessment provides a link between a pension plan’s risk capacity, management’s willingness to accept investment risk and the asset allocation process, which ultimately leads to the return generated by the invested assets.

The health care cost trend rate assumed for 2024 is 7.37% and is expected to reach an ultimate trend rate of 4.0% by 2048.

The Company’s pension plan assets at December 31, 2023 and 2022, respectively, are categorized below according to the fair value hierarchy as defined in Note 13, “Fair Value Measurements”:


	Total				Level 1				Level 2				Level 3
	2023		2022		2023		2022		2023		2022		2023		2022

	(In thousands)
Fixed income securities:
U.S. government securities^(A)	$	—	$	37,148	$	—	$	34,143	$	—	$	3,005	$	—	$	—
Non-U.S. government securities^(B)		—		2,340		—		—		—		2,340		—		—
Corporate fixed income^(C)		—		41,286		—		—		—		41,286		—		—
State and local government securities^(D)		—		2,504		—		—		—		2,504		—		—
Other investments^(E)		—		15,616		—		—		—		15,616		—		—
Total	$	—	$	98,894	$	—	$	34,143	$	—	$	64,751	$	—	$	—
Assets at net asset value^(F)		—		22,233
	$	—	$	121,127

(A)

U.S. government securities includes agency and treasury debt. These investments are valued using dealer quotes in an active market.

(B)

Non-U.S. government securities includes debt securities issued by foreign governments and are valued utilizing a price spread basis valuation technique with observable sources from investment dealers and research vendors.

(C)

Corporate fixed income is primarily comprised of corporate bonds and certain corporate asset-backed securities that are denominated in the U.S. dollar and are investment-grade securities. These investments are valued using dealer quotes.

(D)

State and local government securities include different U.S. state and local municipal bonds and asset backed securities, these investments are valued utilizing a market approach that includes various valuation techniques and sources such as value generation models, broker quotes, benchmark yields and securities, reported trades, issuer trades and/or other applicable data.

(E)

Other investments include cash, forward contracts, derivative instruments, credit default swaps, interest rate swaps and mutual funds. Investments in interest rate swaps are valued utilizing a market approach that includes various valuation techniques and sources such as value generation models, broker quotes in active and non-active markets, benchmark yields and securities, reported trades, issuer trades and/or other applicable data. Forward contracts and derivative instruments are valued at their exchange listed price or broker quote in an active market. The mutual funds are valued at the net asset value per share multiplied by the number of shares held as of the measurement date and are traded on listed exchanges.

(F)

Investments that are measured at fair value using the net asset value per share practical expedient have not been classified in the fair value hierarchy in accordance with Accounting Standards Update 2015-07. These investments are primarily mutual funds that are highly liquid with no restrictions on ability to redeem the funds into cash.

Cash Flows. The Company expects to make no contributions to the pension plans in 2024.

The following represents expected future benefit payments from the plan:


			Other
	Pension		Postretirement
	Benefits		Benefits

	(In thousands)
2024	$	109	$	4,699
2025		106		4,645
2026		103		4,564
2027		99		4,493
2028		95		4,381
Next 5 years		393		19,208
	$	905	$	41,990

Other Plans

The Company sponsors savings plans which were established to assist eligible employees in providing for their future retirement needs. The Company’s expense, representing its contributions to the plans, was $20.5 million, $18.7 million, and $16.8 million for the years ended December 31, 2023, 2022, and 2021, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480482/715-20-55-17

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//715/tableOfContent

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480126/715-20-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480266/715-60-50-3

+ Details

Workers' Compensation Expense (Occupational Disease Costs Activity and Assumptions) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Self Insurance Reserve [Roll Forward]
Service cost	$ 3,974	$ 5,991	$ 7,796
Interest cost	$ 6,041	$ 4,610	4,439
Discount Rate
Self Insurance Reserve [Roll Forward]
Discount rate	0.0501	0.0521
Occupational disease
Self Insurance Reserve [Roll Forward]
Beginning of period	$ 120,008	$ 167,585
Service cost	3,974	5,991
Interest cost	6,041	4,610
Actuarial (gain) loss	10,721	(48,859)
Benefit and administrative payments	(11,526)	(9,319)
End of period	$ 129,218	$ 120,008	$ 167,585

Segment Information (Tables)

12 Months Ended

Dec. 31, 2023

Segment Information

Schedule of Operating Segment Results


					Corporate,
					Other and
(In thousands)	MET		Thermal		Eliminations		Consolidated

Year Ended December 31, 2023
Revenues	$	1,892,326	$	1,253,517	$	—	$	3,145,843
Adjusted EBITDA		717,834		125,469		(129,261)		714,042
Depreciation, depletion and amortization		116,550		28,996		872		146,418
Accretion on asset retirement obligation		2,507		17,255		1,408		21,170
Total assets		1,064,510		437,776		981,887		2,484,173
Capital expenditures		141,210		33,212		1,615		176,037

Year Ended December 31, 2022
Revenues	$	2,157,710	$	1,566,883	$	—	$	3,724,593
Adjusted EBITDA		1,021,932		353,884		(115,384)		1,260,432
Depreciation, depletion and amortization		111,772		20,650		878		133,300
Accretion on asset retirement obligation		2,213		13,775		1,733		17,721
Total assets		1,058,217		381,099		993,792		2,433,108
Capital expenditures		140,031		28,578		4,119		172,728

Year Ended December 31, 2021
Revenues	$	1,149,133	$	1,057,480	$	1,429	$	2,208,042
Adjusted EBITDA		442,830		175,709		(85,109)		533,430
Depreciation, depletion and amortization		99,171		20,231		925		120,327
Accretion on asset retirement obligation		2,030		17,675		2,043		21,748
Total assets		964,761		205,147		947,252		2,117,160
Capital expenditures		227,802		5,949		11,689		245,440

Schedule of Reconciliation of Net Income to Adjusted EBITDA


	Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,
(In thousands)	2023		2022		2021
Net income	$	464,038	$	1,330,914	$	337,573
Provision for (benefit from) income taxes		87,514		(251,926)		1,874
Interest (income) expense, net		(2,438)		13,162		23,344
Depreciation, depletion and amortization		146,418		133,300		120,327
Accretion on asset retirement obligations		21,170		17,721		21,748
Loss on divestitures		—		—		24,225
Non-service related pension and postretirement benefit (credits) costs		(3,786)		2,841		4,339
Net loss resulting from early retirement of debt		1,126		14,420		—
Adjusted EBITDA	$	714,042	$	1,260,432	$	533,430
EBITDA from idled or otherwise disposed operations		15,986		(828)		2,469
Selling, general and administrative expenses		98,871		105,355		92,342
Other		14,404		10,857		(9,702)
Segment Adjusted EBITDA from coal operations	$	843,303	$	1,375,816	$	618,539

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Measurements

Summary of Financial Assets and Liabilities Accounted for at Fair Value


	December 31, 2023
	Total		Level 1		Level 2		Level 3

	(In thousands)
Assets:
Investments in marketable securities	$	32,724	$	28,773	$	3,951	$	—
Derivatives		998		—		—		998
Fund for asset retirement obligations		142,266		142,266		—		—
Total assets	$	175,988	$	171,039	$	3,951	$	998
Liabilities:
Derivatives	$	165	$	—	$	165	$	—


	Fair Value at December 31, 2022
	Total		Level 1		Level 2		Level 3

	(In thousands)
Assets:
Investments in marketable securities	$	36,993	$	28,301	$	8,692	$	—
Derivatives		3,955		—		2,655		1,300
Fund for asset retirement obligations		135,993		135,993		—		—
Total assets	$	176,941	$	164,294	$	11,347	$	1,300
Liabilities:
Derivatives	$	—	$	—	$	—	$	—

Summary of Change in the Fair Values of Financial Instruments Categorized as Level 3


	2023		2022
(In thousands)
Balance, beginning of period	$	1,300	$	1,219
Realized and unrealized gains (losses) recognized in earnings, net		(4,192)		7,019
Purchases		5,400		4,673
Settlements		(1,510)		(11,611)
Ending balance	$	998	$	1,300

Equity Method Investments and Membership Interests in Joint Ventures (Tables)

12 Months Ended

Dec. 31, 2023

Equity Method Investments and Membership Interests in Joint Ventures

Schedule Of Equity Method Investments



(In thousands)	DTA

December 31, 2021	$	15,403
Advances to affiliates, net		9,575
Equity in comprehensive loss		(7,711)
December 31, 2022	$	17,267
Advances to affiliates, net		17,345
Equity in comprehensive loss		(11,797)

December 31, 2023	$	22,815

Employee Benefit Plans (Schedule of Allocation of Plan Assets) (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Total fair value	$ 121,127
Total
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	98,894
Total \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	34,143
Total \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	64,751
U.S. government securities
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	37,148
U.S. government securities \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	34,143
U.S. government securities \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	3,005
Non-U.S. government securities
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	2,340
Non-U.S. government securities \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	2,340
Corporate notes and bonds
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	41,286
Corporate notes and bonds \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	41,286
State and local government securities
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	2,504
State and local government securities \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	2,504
Other investments
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	15,616
Other investments \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	15,616
Other fixed income
Defined Benefit Plan Disclosure [Line Items]
Total fair value of plan assets	$ 22,233

Revenue Recognition (Tables)

12 Months Ended

Dec. 31, 2023

Revenue Recognition

Schedule of effects of revenue recognition


					Corporate,
					Other and
	MET		Thermal		Eliminations		Consolidated

	(in thousands)

Year Ended December 31, 2023
North America revenues	$	342,070	$	1,030,246	$	—	$	1,372,316
Seaborne revenues		1,550,256		223,271		—		1,773,527

Total revenues	$	1,892,326	$	1,253,517	$	—	$	3,145,843

Year Ended December 31, 2022
North America revenues	$	232,831	$	1,180,310	$	—	$	1,413,141
Seaborne revenues		1,924,879		386,573		—		2,311,452

Total revenues	$	2,157,710	$	1,566,883	$	—	$	3,724,593

Year Ended December 31, 2021
North America revenues	$	163,833	$	893,741	$	1,429	$	1,059,003
Seaborne revenues		985,300		163,739		—		1,149,039

Total revenues	$	1,149,133	$	1,057,480	$	1,429	$	2,208,042

Earnings per Common Share

12 Months Ended

Dec. 31, 2023

Earnings per Common Share

Earnings per Common Share

18. Earnings Per Common Share

The Company computes basic net income per share using the weighted average number of common shares outstanding during the period. Diluted net income per share is computed using the weighted average number of common shares and the effect of potentially dilutive securities outstanding during the period. Potentially dilutive securities may consist of warrants, restricted stock units or other contingently issuable shares and convertible debt. The dilutive effect of outstanding warrants, restricted stock units is reflected in diluted earnings per share by application of the treasury stock method whereas the Convertible Debt uses the if-converted method.

The following table provides the basis for basic and diluted EPS by reconciling the numerators and denominators of the computations:


	Year Ended	Year Ended	Year Ended
	December 31,	December 31,	December 31,
	2023	2022	2021
(In Thousands)
Net income attributable to common shares	$ 464,038	$ 1,330,914	$ 337,573
Adjustment of interest expense attributable to convertible notes	108	4,726	-
Adjustment for inducement payments	-	4,914	-
Diluted net income attributable to common shareholders	$ 464,146	$ 1,340,554	$ 337,573


Weighted average shares outstanding:
Basic weighted average shares outstanding	18,233	17,136	15,318
Effect of dilutive securities	866	1,730	654
Convertible Notes	84	2,119	1,607
Diluted weighted average shares outstanding	19,183	20,985	17,579

Capital Stock (Dividends) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022
Capital Stock
Dividends (in dollars per share)	$ 1.13	$ 3.97	$ 2.45	$ 3.11	$ 10.75	$ 6.00	$ 8.11	$ 0.25	$ 10.66	$ 25.11
Amount (in thousands)	$ 22,335	$ 71,877	$ 45,011	$ 66,902	$ 191,754	$ 110,071	$ 150,716	$ 3,851	$ 206,125	$ 456,392
Dividends inclusive amount									$ 792,100

Leases (Tables)

12 Months Ended

Dec. 31, 2023

Leases

Schedule of right-of-use assets and lease liabilities


		December 31,		December 31,
		2023		2022
Assets	Balance Sheet Classification
Operating lease right-of-use assets	Other noncurrent assets	$	9,626	$	12,106
Financing lease right-of-use assets	Other noncurrent assets		1,621		2,918
Total Lease Assets		$	11,247	$	15,024

Liabilities	Balance Sheet Classification
Financing lease liabilities - current	Accrued expenses and other current liabilities	$	1,041	$	977
Operating lease liabilities - current	Accrued expenses and other current liabilities		2,789		2,722
Financing lease liabilities - long-term	Other noncurrent liabilities		2,079		3,121
Operating lease liabilities - long-term	Other noncurrent liabilities		7,351		9,993
		$	13,260	$	16,813

Weighted average remaining lease term in years
Operating leases			3.32		4.14
Finance leases			1.25		2.25

Weighted average discount rate
Operating leases			5.5%		5.5%
Finance leases			6.4%		6.4%

Schedule of Information Related to Leases


		Year Ended December 31,
		2023		2022

	(In thousands)
Operating lease information:
Operating lease cost		$	3,263	$	3,323
Operating cash flows from operating leases			3,356		3,389

Financing lease information:
Financing lease cost		$	1,572	$	1,572
Operating cash flows from financing leases			1,210		1,210

Schedule of Future Minimum Lease Payments

Future minimum lease payments under non-cancellable leases as of December 31, 2023 were as follows:


	Operating		Finance
Year	Leases		Leases

	(In thousands)
2024	$	3,281	$	1,210
2025		3,266		2,111
2026		3,080		—
2027		1,533		—
2028		—		—
Thereafter		—		—
Total minimum lease payments	$	11,160	$	3,321
Less imputed interest		(1,020)		(201)

Total lease liabilities	$	10,140	$	3,120

Fair Value Measurements - Change in fair Values of financial instruments categorized as level 3 (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 1,300	$ 1,219
Realized and unrealized gains (losses) recognized in earnings, net	$ (4,192)	$ 7,019
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Operating Income (Expense), Net	Other Operating Income (Expense), Net
Purchases	$ 5,400	$ 4,673
Settlements	1,510	11,611
Ending balance	$ 998	$ 1,300

Segment Information - Schedule of operating segment results (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) item	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of distinct lines of business \| item	2
Revenues	$ 3,145,843	$ 3,724,593	$ 2,208,042
Adjusted EBITDA	714,042	1,260,432	533,430
Depreciation, depletion and amortization	146,418	133,300	120,327
Accretion on asset retirement obligation	21,170	17,721	21,748
Total assets	2,484,173	2,433,108	2,117,160
Capital expenditures	176,037	172,728	245,440
Operating Segments \| MET
Segment Reporting Information [Line Items]
Revenues	1,892,326	2,157,710	1,149,133
Adjusted EBITDA	717,834	1,021,932	442,830
Depreciation, depletion and amortization	116,550	111,772	99,171
Accretion on asset retirement obligation	2,507	2,213	2,030
Total assets	1,064,510	1,058,217	964,761
Capital expenditures	141,210	140,031	227,802
Operating Segments \| Thermal
Segment Reporting Information [Line Items]
Revenues	1,253,517	1,566,883	1,057,480
Adjusted EBITDA	125,469	353,884	175,709
Depreciation, depletion and amortization	28,996	20,650	20,231
Accretion on asset retirement obligation	17,255	13,775	17,675
Total assets	437,776	381,099	205,147
Capital expenditures	33,212	28,578	5,949
Corporate, Other and Eliminations
Segment Reporting Information [Line Items]
Revenues	0	0	1,429
Adjusted EBITDA	(129,261)	(115,384)	(85,109)
Depreciation, depletion and amortization	872	878	925
Accretion on asset retirement obligation	1,408	1,733	2,043
Total assets	981,887	993,792	947,252
Capital expenditures	$ 1,615	$ 4,119	$ 11,689

Leases - Weighted average lease term and discount rate (Details)	Dec. 31, 2023	Dec. 31, 2022
Leases
Weighted average remaining lease term in years - Operating leases	3 years 3 months 25 days	4 years 1 month 20 days
Weighted average remaining lease term in years - Finance leases	1 year 3 months	2 years 3 months
Weighted average discount rate - Operating leases	5.50%	5.50%
Weighted average discount rate - Finance leases	6.40%	6.40%

Revenue Recognition

12 Months Ended

Dec. 31, 2023

Revenue Recognition

Revenue Recognition

21. Revenue Recognition

ASC 606-10-50-5 requires that entities disclose disaggregated revenue information in categories (such as type of good or service, geography, market, type of contract, etc.) that depict how the nature, amount, timing, and uncertainty of revenue and cash flow are affected by economic factors. ASC 606-10-55-89 explains that the extent to which an entity’s revenue is disaggregated depends on the facts and circumstances that pertain to the entity’s contracts with customers and that some entities may need to use more than one type of category to meet the objective for disaggregating revenue.

In general, the Company’s business segmentation is aligned according to the nature and economic characteristics of its coal and customer relationships and provides meaningful disaggregation of each segment’s results. The Company has further disaggregated revenue between North America and Seaborne revenues which depicts the pricing and contract differences between the two. North America revenue is characterized by contracts with a term of one year or longer and

typically the pricing is fixed; whereas Seaborne revenue generally is derived by spot or short-term contracts with an indexed based pricing mechanism.


					Corporate,
					Other and
	MET		Thermal		Eliminations		Consolidated

	(in thousands)

Year Ended December 31, 2023
North America revenues	$	342,070	$	1,030,246	$	—	$	1,372,316
Seaborne revenues		1,550,256		223,271		—		1,773,527

Total revenues	$	1,892,326	$	1,253,517	$	—	$	3,145,843

Year Ended December 31, 2022
North America revenues	$	232,831	$	1,180,310	$	—	$	1,413,141
Seaborne revenues		1,924,879		386,573		—		2,311,452

Total revenues	$	2,157,710	$	1,566,883	$	—	$	3,724,593

Year Ended December 31, 2021
North America revenues	$	163,833	$	893,741	$	1,429	$	1,059,003
Seaborne revenues		985,300		163,739		—		1,149,039

Total revenues	$	1,149,133	$	1,057,480	$	1,429	$	2,208,042

As of December 31, 2023, the Company has outstanding performance obligations for approximately 59.3 million tons of coal for 2024, representing 54.3 million tons of fixed price contracts and 5.0 million tons of variable price contracts. Additionally, the Company has outstanding performance obligations of approximately 59.7 million tons in periods beyond 2024, comprised of 58.9 million tons of fixed price contracts and 0.8 million tons of variable price contracts.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-10

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-15

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

+ Details

Derivatives - Schedule of price risk derivatives (Details)	12 Months Ended
	Dec. 31, 2023 T
Coal Contract \| Designated as Hedging Instrument
Derivative [Line Items]
Derivatives held (in tons)	7,000

Workers Compensation Expense (Details) $ in Millions		1 Months Ended	12 Months Ended
Workers Compensation Expense (Details) $ in Millions	Jan. 18, 2023	Feb. 29, 2020 USD ($)	Dec. 31, 2023 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Self-insured operators must post security percent	120.00%
Additional collateral amount		$ 71.1
Number of days required to submit additional collateral to retain self-insurance status		30 days
Increase (decrease) in workers compensation obligations due to change in discount rate			$ 3.2
Reimbursable liabilities			6.9
Insurance receivable, current			0.4
Insurance receivable, noncurrent			6.5
Total workers' compensation expense
Defined Benefit Plan Disclosure [Line Items]
Surety bonds and letters of credit outstanding			$ 124.2
Risk Free Interest Rate \| Total workers' compensation expense
Defined Benefit Plan Disclosure [Line Items]
Discount rate			0.0455

Stock-Based Compensation and Other Incentive Plans (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 25.4	$ 27.4	$ 20.5
Unrecognized share-based compensation expense	$ 24.5
Weighted-average period for recognition of unrecognized share-based compensation expense	2 years
Time Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Volatility rate	67.00%
2016 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for incentive plan (in shares)	3.0
Number of shares available for grant (in shares)	1.5

Workers' Compensation Expense (Schedule of Amounts Recognized in Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accrued Workers' Compensation [Line Items]
Total obligations	$ 173,374	$ 173,340
Less amount included in accrued expenses	18,724	17,584
Noncurrent obligations	154,650	155,756
Occupational disease
Accrued Workers' Compensation [Line Items]
Occupational disease costs	129,218	120,008	$ 167,585
Total workers' compensation expense
Accrued Workers' Compensation [Line Items]
Occupational disease costs	$ 44,156	$ 53,332

Accounting Policies (Policies)	12 Months Ended
Accounting Policies (Policies)	Dec. 31, 2023
Accounting Policies
Accounting Estimates	Accounting Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and revenues and expenses in the accompanying consolidated financial statements and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents are stated at cost. Cash equivalents consist of highly-liquid investments with an original maturity of three months or less when purchased and investments in commercial paper which the Company classifies as cash and cash equivalents.
Restricted Cash	Restricted Cash Amounts included in restricted cash represent required deposits for a performance bid bond for a potential customer for $1.1 million as of both December 31, 2023 and 2022, respectively.
Accounts Receivable	Accounts Receivable Accounts receivable are recorded at amounts that are expected to be collected, based on past collection history, the economic environment and specified risks identified in the receivables portfolio.
Inventories	Inventories Coal and supplies inventories are valued at the lower of average cost or market. Coal inventory costs include labor, supplies, equipment costs, transportation costs incurred prior to the transfer of title to customers and operating overhead. The costs of removing overburden, called stripping costs, incurred during the production phase of the mine are considered variable production costs and are included in the cost of the coal extracted during the period the stripping costs are incurred.
Investments and Membership Interests in Joint Ventures	Investments and Membership Interests in Joint Ventures Investments and membership interests in joint ventures are accounted for under the equity method of accounting if the Company has the ability to exercise significant influence, but not control, over the entity. The Company’s share of the entity’s income or loss is reflected in “Other operating (income) expense, net” in the Consolidated Income Statements. Information about investment activity is provided in Note 7, “Equity Method Investments and Membership Interests in Joint Ventures” to the Consolidated Financial Statements. Investments in debt securities are classified as available-for-sale and are recorded at their fair values. Unrealized gains and losses on these investments are recorded in other comprehensive income or loss. A decline in the value of an investment that is considered other-than-temporary would be recognized in operating expenses.
Exploration Costs	Exploration Costs Costs to acquire permits for exploration activities are capitalized. Drilling and other costs related to locating coal deposits and evaluating the economic viability of such deposits are expensed as incurred.
Prepaid Royalties	Prepaid Royalties Leased mineral rights are often acquired through royalty payments. When royalty payments represent prepayments recoupable against royalties owed on future revenues from the underlying coal, they are recorded as a prepaid asset, with amounts expected to be recouped within one year classified as current. When coal from these leases is sold, the royalties owed are recouped against the prepayment and charged to cost of sales. An impairment charge is recognized for prepaid royalties that are not expected to be recouped.
Property, Plant and Equipment	Property, Plant and Equipment Plant and Equipment Plant and equipment were recorded at fair value at emergence during fresh start accounting; subsequent purchases of property, plant and equipment have been recorded at cost. Interest costs incurred during the construction period for major asset additions are capitalized. The Company did not capitalize interest costs during the years ended December 31, 2023, and 2022, respectively. Expenditures that extend the useful lives of existing plant and equipment or increase the productivity of the asset are capitalized. The cost of maintenance and repairs that do not extend the useful life or increase the productivity of the asset is expensed as incurred. Preparation plants and loadouts are depreciated using the units-of-production method over the estimated recoverable reserves, subject to a minimum level of depreciation. Other plant and equipment are depreciated principally using the straight-line method over the estimated useful lives of the assets, limited by the remaining life of the mine. The useful lives of mining equipment, including longwalls, draglines and shovels, range from 1 to 16 years. The useful lives of buildings and leasehold improvements generally range from 5 to 20 years. Deferred Mine Development Costs of developing new mines or significantly expanding the capacity of existing mines are capitalized and amortized using the units-of-production method over the estimated recoverable reserves that are associated with the property being benefited. Costs may include construction permits and licenses; mine design; construction of access roads, shafts, slopes and main entries; and removing overburden to access reserves in a new pit. Additionally, deferred mine development includes the asset cost associated with asset retirement obligations. Coal sales revenue related to incidental production during the development phase is recorded as coal sales revenue with an offset to cost of coal sales based on the estimated cost per ton sold for the mine when the asset is in place for its intended use. Coal Lands and Mineral Rights Rights to coal reserves may be acquired directly through governmental or private entities. A significant portion of the Company’s coal reserves are controlled through leasing arrangements. Lease agreements are generally long-term in nature (original terms range from 10 to 50 years), and substantially all of the leases contain provisions that allow for automatic extension of the lease term providing certain requirements are met. Leases of mineral reserves and related land leases are exempt from the provisions of the leasing standard. The net book value of the Company’s coal interests was $215.6 million and $239.4 million at December 31, 2023 and 2022, respectively. Payments to acquire royalty lease agreements and lease bonus payments are capitalized as a cost of the underlying mineral reserves and depleted over the life of proven and probable reserves. Coal lease rights are depleted using the units-of-production method, and the rights are assumed to have no residual value. The Company currently does not have any future lease bonus payments. Depreciation, depletion and amortization The depreciation, depletion and amortization related to long-lived assets is reflected in the Consolidated Income Statements as a separate line item. No depreciation, depletion or amortization are included in any other operating cost categories. Impairment If facts and circumstances suggest that the carrying value of a long-lived asset or asset group may not be recoverable, the asset or asset group is reviewed for potential impairment. If this review indicates that the carrying amount of the asset will not be recoverable through projected undiscounted cash flows generated by the asset and its related asset group over its remaining life, then an impairment loss is recognized by reducing the carrying value of the asset to its fair value. The Company may, under certain circumstances, idle mining operations in response to market conditions or other factors. Because an idling is not a permanent closure, it is not considered an automatic indicator of impairment.
Deferred Financing Costs	Deferred Financing Costs The Company capitalizes costs incurred in connection with new borrowings, the establishment or enhancement of credit facilities and the issuance of debt securities. These costs are amortized as an adjustment to interest expense over the life of the borrowing or term of the credit facility using the effective interest method. Debt issuance costs related to a recognized liability are presented in the balance sheet as a direct reduction from the carrying amount of that liability whereas debt issuance costs related to a credit facility with no balance outstanding are shown as an asset. The unamortized balance of deferred financing costs shown as an asset was $1.0 million at December 31, 2023, with $0.6 million classified as current; the unamortized balance of deferred financing costs shown as an asset at December 31, 2022 was $1.6 million with $0.6 million classified as current. The current amounts are classified within “Other current assets” and the noncurrent amounts are classified within “Other noncurrent assets.” For information on the unamortized balance of deferred financing fees related to outstanding debt, see Note 10, “Debt and Financing Arrangements” to the Consolidated Financial Statements.
Revenue Recognition	Revenue Recognition Revenues include sales to customers of coal produced at Company operations and coal purchased from third parties. The Company recognizes revenue at the time risk of loss passes to the customer at contracted amounts. Transportation costs are included in cost of sales and amounts billed by the Company to its customers for transportation are included in revenues. Control of the goods may transfer and revenue may be recognized before, during or subsequent to the period in which final average pricing is determined. For all metallurgical coal sales under average pricing contracts where pricing is not finalized when revenue is recognized, revenue is recorded based on estimated consideration to be received at the date of the sale with reference to metallurgical coal price assessments.
Other Operating (Income) Expense, net	Other Operating (Income) Expense, net Other operating (income) expense, net in the accompanying Consolidated Income Statements reflects income and expense from sources other than physical coal sales, including: contract settlements; royalties earned from properties leased to third parties; income from equity investments (Note 7, “Equity Method Investments and Membership Interests in Joint Ventures”); non-material gains and losses from divestitures and dispositions of assets; and realized gains and losses on derivatives that do not qualify for hedge accounting and are not held for trading purposes (Note 8, “Derivatives”); and land management expenses.
Asset Retirement Obligations	Asset Retirement Obligations The Company’s legal obligations associated with the retirement of long-lived assets are recognized at fair value at the time the obligations are incurred. Accretion expense is recognized through the expected settlement date of the obligation. Obligations are incurred at the time development of a mine commences for underground and surface mines or construction begins for support facilities, refuse areas and slurry ponds. The obligation’s fair value is determined using a discounted cash flow technique and is based upon permit requirements and various estimates and assumptions that would be used by market participants, including estimates of disturbed acreage, reclamation costs and assumptions regarding equipment productivity. Upon initial recognition of a liability, a corresponding amount is capitalized as a component of the carrying value of the related long-lived asset. The Company reviews its asset retirement obligation at least annually and makes necessary adjustments for permit changes as granted by state authorities and for revisions of estimates of the amount and timing of costs. For ongoing operations, adjustments to the liability result in an adjustment to the corresponding asset. For idle operations, adjustments to the liability are recognized as income or expense in the period the adjustment is recorded. Any difference between the recorded obligation and the actual cost of reclamation is recorded in profit or loss in the period the obligation is settled. See additional discussion in Note 12, “Asset Retirement Obligations” to the Consolidated Financial Statements.
Loss Contingencies	Loss Contingencies The Company accrues for cost related to contingencies when a loss is probable and the amount is reasonably determinable. Disclosure of contingencies is included in the financial statements when it is at least reasonably possible that a material loss or an additional material loss in excess of amounts already accrued may be incurred. The amount accrued represents the Company’s best estimate of the loss, or, if no best estimate within a range of outcomes exists, the minimum amount in the range.
Derivative Instruments	Derivative Instruments The Company generally utilizes derivative instruments to manage exposures to commodity prices and interest rate risk on long-term debt. Derivative financial instruments are recognized on the balance sheet at fair value. Certain coal contracts may meet the definition of a derivative instrument, but because they provide for the physical purchase or sale of coal in quantities expected to be used or sold by the Company over a reasonable period in the normal course of business, they are not recognized on the balance sheet. See Note 8, “Derivatives” to the Consolidated Financial Statements for further disclosures related to the Company’s derivative instruments.
Fair Value	Fair Value Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly hypothetical transaction between market participants at a given measurement date. Valuation techniques used must maximize the use of observable inputs and minimize the use of unobservable inputs. See Note 13, “Fair Value Measurements” to the Consolidated Financial Statements for further disclosures related to the Company’s recurring fair value estimates.
Income Taxes	Income Taxes Deferred income taxes are provided for temporary differences arising from differences between the financial statement and tax basis of assets and liabilities existing at each balance sheet date using enacted tax rates anticipated to be in effect when the related taxes are expected to be paid or recovered. A valuation allowance is established if it is more likely than not that a deferred tax asset will not be realized. Management reassesses the ability to realize its deferred tax assets annually in the fourth quarter or when circumstances indicate that the ability to realize deferred tax assets has changed. In determining the need for a valuation allowance, the Company considers projected realization of tax benefits based on expected levels of future taxable income, available tax planning strategies and the reversal of temporary differences. As it relates to changes in accumulated other comprehensive income (loss), the Company’s policy is to release tax effects from accumulated other comprehensive income (loss) when the underlying components affect earnings. Benefits from tax positions that are uncertain are not recognized unless the Company concludes that it is more likely than not that the position would be sustained in a dispute with taxing authorities, should the dispute be taken to the court of last resort. The Company would measure any such benefit at the largest amount of benefit that is greater than 50% likely of being realized upon settlement with taxing authorities. See Note 11, “Taxes” to the Consolidated Financial Statements for further disclosures about income taxes.
Benefit Plans	Benefit Plans In February 2022, the Board of Directors approved the termination of the Company’s Cash Balance Pension Plan. The Company has executed plan amendments regarding the termination and filed an Application for Determination for Terminating Pension Plan with the Internal Revenue Service (“IRS”), which was approved by the IRS during the first quarter of 2023. The Company also prepared and filed appropriate notices and documents related to the Pension Plan's termination and wind-down with the Pension Benefit Guaranty Corporation (“PBGC”). To complete the termination of the plan, the Company made a $3.2 million cash contribution into the plan in order to complete lump sum payments and to purchase annuity contracts for plan participants. An immaterial gain was recognized on the plan termination, which is reflected in the Consolidated Income Statements line item “Non-service related pension and postretirement benefits credits (costs)”. The Company no longer administers or pays the retirement benefits of the Company’s Cash Balance Pension Plan going forward.
Stock-Based Compensation	Stock-Based Compensation The compensation cost of all stock-based awards is determined based on the grant-date fair value of the award, and is recognized over the requisite service period. The grant-date fair value of restricted stock awards with a market condition is determined using a Monte Carlo simulation. Compensation cost for an award with performance conditions is accrued if it is probable that the conditions will be met. The Company accounts for forfeitures as they occur. See further discussion in Note 15, “Stock-Based Compensation and Other Incentive Plans” to the Consolidated Financial Statements.
Recently Adopted Accounting Guidance	Recently Adopted Accounting Guidance In August 2020, the FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity's Own Equity (Subtopic 815-40)—Accounting for Convertible Instruments and Contracts in an Entity's Own Equity. ASU 2020-06 reduces the number of accounting models for convertible debt instruments. Additionally, ASU 2020-06 amends the diluted earnings per share calculation for convertible instruments by requiring the use of the if-converted method. The if-converted method assumes the conversion of convertible instruments occurs at the beginning of the reporting period and diluted weighted average shares outstanding includes the common shares issuable upon conversion of the convertible instruments. ASU 2020-06 is effective for public business entities, for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. The Company adopted ASU 2020-06 on January 1, 2022 under the modified retrospective approach. Upon issuance of the Company's $155.3 million principal amount of 5.25% convertible senior notes due 2025 (the "Convertible Notes" or “Convertible Debt”) in November 2020, the Company bifurcated the debt and equity components of the Convertible Notes to long-term debt and additional paid-in capital in its consolidated balance sheet. The amount recorded to additional paid-in capital represented a debt discount that was being amortized to interest expense over the life of the Convertible Notes. As part of the adoption of ASU 2020-06, the Company (i) reversed the equity component recorded to additional paid-in capital of $39.2 million, (ii) recorded a cumulative effect of the adoption of ASU 2020-06 of $6.7 million to retained earnings, representing a reversal of the debt discount that was amortized to interest expense, and (iii) recorded an offsetting increase in debt. See Note 10, “Debt and Financing Arrangements” for additional information. Additionally, upon adoption of ASU 2020-06, the treasury stock method utilized by the Company to calculate earnings per share through December 31, 2021 is no longer permitted. Accordingly, the Company has transitioned to the if-converted method utilizing the modified retrospective approach. For the year ended December 31, 2022, under the previous treasury stock method, the diluted earnings per share would have been approximately $65.28. As a result of the adoption of ASU 2020-06, diluted earnings per share decreased by $1.40 for the year ended December 31, 2022. During 2023, the Company repurchased the remaining Convertible Notes with a principal amount of $13.2 million for aggregate consideration consisting of $58.4 million in cash. Recently Adopted Accounting Guidance Not Yet Effective In November 2023, the FASB issued ASU 2023-07 Segment Reporting – Improving Reportable Segment Disclosures (Topic 280). The update is intended to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant expenses. The ASU requires disclosure to include significant segment expenses that are regularly provided to the chief operating decision maker (CODM), a description of other segment items by reportable segment, and any additional measures of a segment’s profit or loss used by the CODM when deciding how to allocate resources. The ASU also requires all annual disclosures currently required by Topic 280 to be included in interim periods. The update is effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted and requires retrospective application to all prior periods presented in the financial statements. The Company is currently assessing the timing and impact of adopting the updated provisions. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which includes amendments that further enhance income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. The amendments are effective for the Company’s annual periods beginning June 1, 2025, with early adoption permitted, and should be applied either prospectively or retrospectively. The Company is currently evaluating the ASU to determine its impact on the Company’s disclosures.

Leases

12 Months Ended

Dec. 31, 2023

Leases

Leases

19. Leases

The Company has operating and finance leases for mining equipment, office equipment and office space with remaining lease terms ranging from less than one year to approximately three years. Some of these leases include both

lease and non-lease components which are accounted for as a single lease component as the Company has elected the practical expedient to combine these components for all leases. As most of the leases do not provide an implicit rate, the Company calculated the Right-of-use (“ROU”) assets and lease liabilities using its’ secured incremental borrowing rate at the lease commencement date.

As of December 31, 2023 and December 31, 2022, the Company had the following ROU assets and lease liabilities within the Company’s Consolidated Balance Sheets:


		December 31,		December 31,
		2023		2022
Assets	Balance Sheet Classification
Operating lease right-of-use assets	Other noncurrent assets	$	9,626	$	12,106
Financing lease right-of-use assets	Other noncurrent assets		1,621		2,918
Total Lease Assets		$	11,247	$	15,024

Liabilities	Balance Sheet Classification
Financing lease liabilities - current	Accrued expenses and other current liabilities	$	1,041	$	977
Operating lease liabilities - current	Accrued expenses and other current liabilities		2,789		2,722
Financing lease liabilities - long-term	Other noncurrent liabilities		2,079		3,121
Operating lease liabilities - long-term	Other noncurrent liabilities		7,351		9,993
		$	13,260	$	16,813

Weighted average remaining lease term in years
Operating leases			3.32		4.14
Finance leases			1.25		2.25

Weighted average discount rate
Operating leases			5.5%		5.5%
Finance leases			6.4%		6.4%

Information related to leases was as follows:


		Year Ended December 31,
		2023		2022

	(In thousands)
Operating lease information:
Operating lease cost		$	3,263	$	3,323
Operating cash flows from operating leases			3,356		3,389

Financing lease information:
Financing lease cost		$	1,572	$	1,572
Operating cash flows from financing leases			1,210		1,210

Future minimum lease payments under non-cancellable leases as of December 31, 2023 were as follows:


	Operating		Finance
Year	Leases		Leases

	(In thousands)
2024	$	3,281	$	1,210
2025		3,266		2,111
2026		3,080		—
2027		1,533		—
2028		—		—
Thereafter		—		—
Total minimum lease payments	$	11,160	$	3,321
Less imputed interest		(1,020)		(201)

Total lease liabilities	$	10,140	$	3,120

Rental expense, including amounts related to these operating leases and other shorter-term arrangements, amounted to $12.8 million in 2023, $10.4 million in 2022 and $8.1 million in 2021.

Royalties are paid to lessors either as a fixed price per ton or as a percentage of the gross selling price of the mined coal. Royalties under the majority of the Company’s significant leases are paid on the percentage of gross selling price basis. Royalty expense, including production royalties, was $177.1 million in 2023, $189.7 million in 2022, and $127.8 million in 2021.

As of December 31, 2023, certain of the Company’s lease obligations were secured by outstanding surety bonds totaling $40.4 million.

Capital Stock

12 Months Ended

Dec. 31, 2023

Capital Stock

Capital Stock

14. Capital Stock

Dividends

The Company declared and paid cash dividends per share during the periods presented below (inclusive of dividends related to restricted stock units):


2023:	Dividends per share		Amount (in thousands)
1st quarter	$	3.11	$	66,902
2nd quarter		2.45		45,011
3rd quarter		3.97		71,877
4th quarter		1.13		22,335
Total cash dividends declared and paid	$	10.66	$	206,125


			Amount
2022:	Dividends per share		(in thousands)
1st quarter	$	0.25	$	3,851
2nd quarter		8.11		150,716
3rd quarter		6.00		110,071
4th quarter		10.75		191,754
Total cash dividends declared and paid	$	25.11	$	456,392

As of December 31, 2023, $792.1 million has been returned as dividends inclusive of the announced dividend on February 15, 2024.

Future dividend declarations will be subject to ongoing Board review and authorization will be based on a number of factors, including business and market conditions, the Company’s future financial performance and other capital priorities.

Share Repurchase Program

During the second quarter of 2022, the Board of Directors increased the remaining outstanding authorization for share repurchases to $500 million. The timing of any future share repurchases, and the ultimate number of shares of common stock to be purchased, will depend on a number of factors, including business and market conditions, future financial performance, and other capital priorities. The shares will be acquired in the open market or through private transactions in accordance with Securities and Exchange Commission requirements. The share repurchase program has no termination date, but may be amended, suspended or discontinued at any time and does not commit the Company to repurchase shares of its common stock. The actual number and value of the shares to be purchased will depend on the performance of the Company’s stock price and other market conditions.

On August 16, 2022, the Inflation Reduction Act of 2022 (“IRA”) was signed into law. This legislation introduces a 1% excise tax on stock repurchases among its key tax provisions. The IRA is effective for years beginning after December 31, 2022.

During 2023, the Company repurchased 989,792 shares at an average price of $124.78 for an aggregate purchase price of approximately $123.5 million. As of December 31, 2023, the Company had repurchased 12,196,627 shares at an average share price of $90.98 per share for an aggregate purchase price of approximately $1,109.7 million since inception of the stock repurchase program, and the remaining authorized amount for stock repurchases under this program is approximately $217.7 million.

Outstanding Warrants

In October 2016, the Company emerged from Chapter 11 which became known as the “Effective Date”. On the Effective Date, the Company entered into a warrant agreement (the “Warrant Agreement”) with American Stock Transfer & Trust Company, LLC as warrant agent and, pursuant to the terms of the Plan, issued warrants (“Warrants”) to purchase up to an aggregate of 1,914,856 shares of Class A Common Stock, par value $0.01 per share, of Arch Resources (the “Class A Common Stock”) to certain holders of claims in the Chapter 11 case. Each Warrant expired on October 5, 2023, and was initially exercisable for one share of Class A Common Stock at an initial exercise price of $57.00 per share. The Warrants were exercisable by a holder paying the exercise price in cash or on a cashless basis, at the election of the holder. The Warrants contained anti-dilution adjustments for stock splits, reverse stock splits, stock dividends, dividends and distributions of cash, other securities or other property, spin-offs and tender and exchange offers by Arch Resources or its subsidiaries to purchase Class A Common Stock at above-market prices.

During 2023, holders of warrants exercised 1,248,226 of the warrants. On October 5, 2023, the remaining warrants expired. There were no warrants outstanding at December 31, 2023.

As provided in ASC 825-20, “Financial Instruments,” the warrants are considered equity because they can only be physically settled in Company shares, can be settled in unregistered shares, the Company has adequate authorized shares to settle the outstanding warrants and each warrant is fixed in terms of settlement to one share of Company stock subject only to remote contingency adjustment factors designed to assure the relative value in terms of shares remains fixed.

- Definition

The entire disclosure for equity.

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+ Details

Earnings per Common Share (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Earnings per Common Share
Net income attributable to common shares	$ 464,038	$ 1,330,914	$ 337,573
Adjustment of interest expense attributable to Convertible Notes	108	4,726
Adjustment for inducement payments		4,914
Diluted net income attributable to common shareholders	$ 464,146	$ 1,340,554	$ 337,573
Weighted average shares outstanding:
Basic weighted average shares outstanding (in shares)	18,233	17,136	15,318
Effect of dilutive securities (in shares)	866	1,730	654
Convertible Notes (in shares)	84	2,119	1,607
Diluted weighted average shares outstanding (in shares)	19,183	20,985	17,579

Capital Stock (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Oct. 05, 2016
Class of Stock [Line Items]
Authorized amount of share repurchase program			$ 500
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Class A
Class of Stock [Line Items]
Warrants issued (in shares)	0			1,914,856
Common stock, par value (in dollars per share)				$ 0.01
Warrant exercise price (in dollars per share)				$ 57.00
Warrant exercised (in shares)	1,248,226

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

Employee Benefit Plans - Schedule of net benefit credit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 3,974	$ 5,991	$ 7,796
Interest cost	$ 6,041	$ 4,610	$ 4,439
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Settlement Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Pension and Other Postretirement Benefits Cost (Reversal of Cost)	Pension and Other Postretirement Benefits Cost (Reversal of Cost)	Pension and Other Postretirement Benefits Cost (Reversal of Cost)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Amortization of Prior Service Cost (Credit), Statement of Income or Comprehensive Income [Extensible Enumeration]	Pension and Other Postretirement Benefits Cost (Reversal of Cost)	Pension and Other Postretirement Benefits Cost (Reversal of Cost)	Pension and Other Postretirement Benefits Cost (Reversal of Cost)
Amortization of other actuarial losses (gains)	$ 965	$ (628)	$ (2,363)
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Amortization of Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Pension and Other Postretirement Benefits Cost (Reversal of Cost)	Pension and Other Postretirement Benefits Cost (Reversal of Cost)	Pension and Other Postretirement Benefits Cost (Reversal of Cost)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0	$ 0
Interest cost	4,108	5,264	4,334
Settlements/Terminations	(1,586)	(771)	(1,768)
Expected return on plan assets	(4,048)	(6,173)	(7,245)
Amortization of prior service credits	(98)	(147)	(128)
Amortization of other actuarial losses (gains)	(553)	(313)	(62)
Net benefit credit	(2,177)	(2,140)	(4,869)
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	231	282	341
Interest cost	2,694	2,006	2,113
Settlements/Terminations	0	0	0
Expected return on plan assets	0	0	0
Amortization of prior service credits	0	0	0
Amortization of other actuarial losses (gains)	(9,690)	(2,508)	0
Net benefit credit	$ (6,765)	$ (220)	$ 2,454

Capital Stock (Share Repurchase Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended		57 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2023
Capital Stock
Number of Shares (in shares)	989,792	1,118,457	12,196,627
Average Repurchase Price per Share (in dollars per share)	$ 124.78		$ 90.98
Amount (in thousands)	$ 123,508	$ 158,790	$ 1,109,700
Stock Repurchase Program, remaining amount	$ 217,700		$ 217,700

Workers Compensation Expense

12 Months Ended

Dec. 31, 2023

Workers Compensation Expense

Workers' Compensation Expense

16. Workers’ Compensation Expense

The Company is liable under the Federal Mine Safety and Health Act of 1969, as subsequently amended, to provide for pneumoconiosis (occupational disease) benefits to eligible employees, former employees and dependents. The Company currently provides for federal claims principally through a self-insurance program. The Company is also liable under various state workers’ compensation statutes for occupational disease benefits. The occupational disease benefit obligation represents the present value of the actuarially computed present and future liabilities for such benefits over the employees’ applicable years of service.

In October 2019, the Company filed an application with the Office of Workers’ Compensation Programs (“OWCP”) within the Department of Labor for reauthorization to self-insure federal black lung benefits. In February 2020, the Company received a reply from the OWCP confirming its status to remain self-insured contingent upon posting additional collateral of $71.1 million within 30 days of receipt of the letter. The Company is currently appealing the ruling from the OWCP and has received an extension to self-insure during the appeal process.

On January 18, 2023, the OWCP proposed revisions to regulations under the Black Lung Benefits Act governing authorization of self-insurers. The revisions seek to codify the practice of basing a self-insured operator’s security requirement on an actuarial assessment of its total present and future black lung liability. A material change to the regulations is the requirements that all self-insured operators must post security equal to 120% of their projected black lung liabilities.

The proposed regulations were posted to the Federal Register on January 19, 2023 with written comments to be accepted within 60 days of this date. A subsequent extended comment period expired on April 19, 2023; however, the final regulations have not yet been published.

If the above regulation is codified into law, the Company will be required to post additional collateral to maintain its self-insured status. The Company is evaluating alternatives to self-insurance, including the purchase of commercial insurance to cover these claims. Additionally, the Company is assessing the availability of surety bond capacity within the markets, additional sources of liquidity, and other items to satisfy the proposed regulations.

In addition, the Company is liable for workers’ compensation benefits for traumatic injuries which are calculated using actuarially-based loss rates, loss development factors and discounted based on a risk-free rate of 4.55%. Traumatic workers’ compensation claims are insured with varying retentions/deductibles, or through state-sponsored workers’ compensation programs.

Workers’ compensation expense consists of the following components:


	Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,
	2023		2022		2021

Self-insured occupational disease benefits:
Service cost	$	3,974	$	5,991	$	7,796
Interest cost⁽¹⁾		6,041		4,610		4,439
Net amortization⁽¹⁾		(965)		628		2,363
Total occupational disease	$	9,050	$	11,229	$	14,598
Traumatic injury claims and assessments		277		(3,783)		3,925
Total workers’ compensation expense	$	9,327	$	7,446	$	18,523

(1)

The table below reconciles changes in the occupational disease liability for the respective period.


	Year Ended		Year Ended
	December 31,		December 31,
(In thousands)	2023		2022
Beginning of period	$	120,008	$	167,585
Service cost		3,974		5,991
Interest cost		6,041		4,610
Actuarial loss (gain)		10,721		(48,859)
Benefit and administrative payments		(11,526)		(9,319)
	$	129,218	$	120,008

The following table provides the assumptions used to determine the projected occupational disease obligation:


	Year Ended December 31, 2023	Year Ended December 31, 2022
(Percentages)
Discount rate	5.01	5.21

The lower discount rate increased obligations by $3.2 million.

Summarized below is information about the amounts recognized in the accompanying Consolidated Balance Sheets for workers’ compensation benefits:


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
(In thousands)
Occupational disease costs	$	129,218	$	120,008
Traumatic and other workers’ compensation claims		44,156		53,332
Total obligations		173,374		173,340
Less amount included in accrued expenses		18,724		17,584
Noncurrent obligations	$	154,650	$	155,756

As of December 31, 2023, the Company had $124.2 million in surety bonds, letters of credit and cash outstanding to secure workers’ compensation obligations.

As of December 31, 2023, the Company’s recorded liabilities include $6.9 million of obligations that are reimbursable under various insurance policies purchased by the Company. These insurance receivables are recorded in the balance sheet line items “Other receivables” and “Other noncurrent assets” for $0.4 million and $6.5 million, respectively.

The following represents expected future payments:



Year	(In thousands)
2024	$	12,837
2025		13,634
2026		13,750
2027		14,186
2028		14,564
Next 5 years		79,731
	$	148,702

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating activities
Net income	$ 464,038	$ 1,330,914	$ 337,573
Adjustments to reconcile to cash from operating activities:
Depreciation, depletion and amortization	146,418	133,300	120,327
Accretion on asset retirement obligations	21,170	17,721	21,748
Deferred income taxes	87,091	(222,023)	8
Employee stock-based compensation expense	25,443	27,383	20,539
Amortization relating to financing activities	1,751	2,459	6,549
(Gain) loss on disposals and divestitures, net	(731)	(997)	23,276
Reclamation work completed	(21,456)	(13,720)	(39,047)
Contribution to fund for asset retirement obligations	(6,273)	(115,993)	(20,000)
Changes in:
Receivables	(31,763)	77,274	(212,950)
Inventories	(21,246)	(66,281)	(30,726)
Accounts payable, accrued expenses and other current liabilities	(31,323)	84,947	45,547
Income taxes, net	(938)	(30,507)	1,820
Coal derivative assets and liabilities, including margin account	1,572	1,274	(3,553)
Asset retirement obligations	3,441	(1,193)	(13,697)
Pension, postretirement and other postemployment benefits	(10,434)	(25,537)	4,571
Other	8,614	10,519	(23,701)
Cash provided by operating activities	635,374	1,209,540	238,284
Investing activities
Capital expenditures	(176,037)	(172,728)	(245,440)
Minimum royalty payments	(1,175)	(1,069)	(1,186)
Proceeds from disposals and divestitures	4,055	1,972	21,228
Purchases of short-term investments	(35,412)	(39,731)
Proceeds from sales of short-term investments	40,292	17,337	87,486
Investments in and advances to affiliates, net	(17,345)	(9,575)	(3,303)
Cash used in investing activities	(185,622)	(203,794)	(141,215)
Financing activities
Payments on term loan due 2024	(3,000)	(273,788)	(7,895)
Proceeds from equipment financing			19,438
Proceeds from tax exempt bonds			44,985
Payments on convertible debt	(58,430)	(208,130)
Net payments on other debt	(18,943)	(11,235)	(11,195)
Debt financing costs	(0)	(1,035)	(2,057)
Purchases of treasury stock	(125,508)	(156,790)
Dividends paid	(206,125)	(456,392)	(3,830)
Payments for taxes related to net share settlement of equity awards	(30,240)	(7,052)	(4,840)
Proceeds from warrants exercised	44,242	19,540	1,175
Cash (used in) provided by financing activities	(398,004)	(1,094,882)	35,781
Increase (decrease) in cash and cash equivalents, including restricted cash	51,748	(89,136)	132,850
Cash and cash equivalents, including restricted cash, beginning of period	237,159	326,295	193,445
Cash and cash equivalents, including restricted cash, end of period	288,907	237,159	326,295
SUPPLEMENTAL CASH FLOW INFORMATION
Cash and cash equivalents	287,807	236,059	325,194
Restricted Cash	1,100	1,100	1,101
Cash paid during the period for interest	$ 10,466	$ 18,820	$ 31,568

Debt and Financing Arrangements (Details) $ / shares in Units, shares in Millions											9 Months Ended	12 Months Ended
	Feb. 08, 2024 USD ($)	Aug. 03, 2022 USD ($)	Jul. 29, 2021 USD ($) installment	Nov. 03, 2020 USD ($) $ / shares	Nov. 02, 2020 $ / shares	Nov. 01, 2020 shares	Oct. 29, 2020 USD ($) $ / shares	Jul. 02, 2020 USD ($)	Mar. 04, 2020 USD ($) installment	Mar. 07, 2017 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($)	Dec. 31, 2018	Aug. 02, 2022 USD ($)	Mar. 04, 2021 USD ($)	Nov. 30, 2020 USD ($)
Debt Instrument [Line Items]
Term loan, face value																		$ 155,300,000
Interest rate																		5.25%
Restricted cash												$ 1,100,000	$ 1,100,000	$ 1,101,000
Debt financing costs												0.0	1,035,000	$ 2,057,000
Unamortized deferred financing fees												1,000,000.0	1,600,000
Outstanding debt												140,595,000	174,276,000
Derivative Assets												998,000	2,707,000
Paid-in Capital
Debt Instrument [Line Items]
Cash on convertible notes																		$ 39,200,000
Retained Earnings
Debt Instrument [Line Items]
Cash on convertible notes																		$ 6,700,000
Secured Debt \| Subsequent Event
Debt Instrument [Line Items]
Term loan repaid	$ 3,500,000
New Term Loan Debt Facility \| Senior Notes
Debt Instrument [Line Items]
Term loan, face value										$ 300,000,000
Percentage of face amount										99.50
Term loan repaid													273,800,000
Amount of voting equity interests of domestic subsidiaries guaranteed (percent)										100
Amount of voting equity interests of foreign owned subsidiaries guaranteed (percent)										65
Outstanding debt													6,500,000
Loss on Early Repayment of Debt													4,100,000
New Term Loan Debt Facility \| Line of Credit \| SOFR
Debt Instrument [Line Items]
Applicable margin on interest rate															2.75%
New Term Loan Debt Facility \| Line of Credit \| SOFR \| Minimum
Debt Instrument [Line Items]
Applicable margin on interest rate															1.00%
New Term Loan Debt Facility \| Line of Credit \| Base Rate
Debt Instrument [Line Items]
Applicable margin on interest rate															1.75%
New senior secured term loan \| Secured Debt \| Subsequent Event
Debt Instrument [Line Items]
Term loan, face value	20,000,000.0
Amortization payments	$ 3,300,000
New Term Loan Debt Facility \| Senior Notes
Debt Instrument [Line Items]
Quarterly principal amortization payments										$ 800,000
Mandatory prepayment amount (as percent)										100
Default to indebtedness										$ 50,000,000
Default to surety, reclamation, or similar bonds securing obligations										50,000,000
Default to uninsured judgment										50,000,000
Uninsured losses or proceedings against minimum amount										$ 50,000,000
Accounts Receivable Securitization Facility \| Line of Credit \| Secured Debt
Debt Instrument [Line Items]
Current borrowing capacity												99,800,000
Letters of credit outstanding												50,200,000
Accounts Receivable Securitization Facility \| Regions Bank \| Line of Credit \| Secured Debt
Debt Instrument [Line Items]
Current borrowing capacity		$ 150,000,000														$ 110,000,000
Inventory-Based Revolving Credit Facility
Debt Instrument [Line Items]
Covenant amount												23,800,000
Inventory-Based Revolving Credit Facility \| Regions Bank \| Line of Credit \| Secured Debt
Debt Instrument [Line Items]
Term loan, face value		$ 50
Letters of credit outstanding												$ 26,200,000
Borrowing base percentage, coal inventory		85
Borrowing base percentage, parts and supplies inventory		85
Borrowing base, percentage of clause		35
Percent of eligible cash		100.00%
Covenant amount											$ 100,000,000
Inventory-Based Revolving Credit Facility \| Regions Bank \| Line of Credit \| Secured Debt \| SOFR
Debt Instrument [Line Items]
Applicable margin on interest rate												0.75%
Inventory-Based Revolving Credit Facility \| Regions Bank \| Line of Credit \| Secured Debt \| SOFR \| Minimum
Debt Instrument [Line Items]
Applicable margin on interest rate												2.25%
Inventory-Based Revolving Credit Facility \| Regions Bank \| Line of Credit \| Secured Debt \| SOFR \| Maximum
Debt Instrument [Line Items]
Applicable margin on interest rate												3.50%
Inventory-Based Revolving Credit Facility \| Regions Bank \| Line of Credit \| Secured Debt \| Base Rate \| Minimum
Debt Instrument [Line Items]
Applicable margin on interest rate												1.25%
Inventory-Based Revolving Credit Facility \| Regions Bank \| Line of Credit \| Secured Debt \| Base Rate \| Maximum
Debt Instrument [Line Items]
Applicable margin on interest rate												2.50%
Equipment financing arrangement \| Secured Debt
Debt Instrument [Line Items]
Term loan, face value			$ 23,500,000						$ 53,600,000
Number of monthly payments \| installment			42						48
Interest rate			7.35%						6.34%
Tax Exempt Bonds
Debt Instrument [Line Items]
Term loan, face value												$ 98,100,000
Tax Exempt Bonds \| Minimum
Debt Instrument [Line Items]
Covenant for cross-events of default to indebtedness											$ 50,000,000
Series 2020 Tax Exempt Bonds
Debt Instrument [Line Items]
Term loan, face value								$ 53,100,000
Interest rate								5.00%
Mandatory tender percentage								100.00%
Series 2021 Tax Exempt Bonds
Debt Instrument [Line Items]
Term loan, face value																	$ 45,000,000.0
Interest rate																	4.125%
Convertible Notes
Debt Instrument [Line Items]
Term loan, face value				$ 155,300,000
Interest rate				5.25%
Net proceeds of convertible debt				$ 132,700,000
Total interest expense													4,700,000
Contractual interest coupon													4,100,000
Amortization of debt discount													600,000
Principal amount of convertible notes												13,200,000	142,100,000
Cash on convertible notes												58,400,000	208,100,000
Deferred Offering Costs				$ 5,100,000
Unamortized Debt Issuance Expense													$ 3,800,000
Debt conversion, number of shares \| shares													2.6
Loss on debt conversion												1,100,000	$ 10,300,000
Inducement premium payment													5,000,000.0
Professional fees													$ 1,500,000
Convertible Notes \| Maximum
Debt Instrument [Line Items]
Total interest expense												100,000
Capped Call Transactions
Debt Instrument [Line Items]
Initial strike price (in dollars per share) \| $ / shares				$ 37.325
Number of underlying shares \| shares						4.2
Cap price \| $ / shares					$ 52.255		$ 52.2550
Premium percentage (as percent)							75.00%
Capped call, transaction cost				$ 17,500,000			$ 17,500,000
Debt instrument capped call transaction intrinsic value												$ 62,100,000

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Consolidated Statements of Comprehensive Income
Net Income (Loss)	$ 464,038	$ 1,330,914	$ 337,573
Derivative instruments
Comprehensive income before tax		1,763	2,128
Other comprehensive income, derivative instruments, net of tax		1,763	2,128
Pension, postretirement and other post-employment benefits
Comprehensive (loss) income before tax	(24,364)	57,930	47,562
Provision for (benefit from) income taxes	1,662	(12,548)
Other comprehensive loss, pension, postretirement and other post-employment benefits, net of tax	(22,702)	45,382	47,562
Available-for-sale securities
Comprehensive income before tax	39	161	169
Provision for (benefit from) income taxes	16	(35)
Other comprehensive (loss) income, available-for-sale securities, net of tax	55	126	169
Total other comprehensive (loss) income	(22,647)	47,271	49,859
Total comprehensive income	$ 441,391	$ 1,378,185	$ 387,432

Taxes

12 Months Ended

Dec. 31, 2023

Taxes

Taxes

11. Taxes

Significant components of the provision for (benefit from) income taxes are as follows:


		Year Ended		Year Ended	Year Ended
		December 31,		December 31,	December 31,
		2023		2022	2021
(In thousands)
Current:
Federal	$	106	$	(30,107)	$	1,525
State		317		204		342
Total current	$	423	$	(29,903)	$	1,867
Deferred:
Federal	$	85,002	$	(209,130)	$	7
State		2,089		(12,893)		—
Total deferred	$	87,091	$	(222,023)	$	7
Provision for (benefit from) income taxes	$	87,514	$	(251,926)	$	1,874

A reconciliation of the statutory federal income tax provision (benefit) at the statutory rate to the actual provision for (benefit from) income taxes follows:


	Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,
	2023		2022		2021

Income tax provision at statutory rate	$	115,826	$	226,587	$	71,284
Percentage depletion and other permanent items		(30,585)		(52,647)		(29,392)
State taxes, net of effect of federal taxes		2,725		2,988		16,490
Change in valuation allowance		(879)		(420,688)		(69,603)
Other, net		427		(8,166)		13,095
Provision for (benefit from) income taxes	$	87,514	$	(251,926)	$	1,874


	December 31,		December 31,
	2023		2022
(In thousands)
Deferred tax assets:
Tax loss carryforwards	$	157,648	$	219,302
Tax credit carryforwards		1,584		1,656
Investment in partnerships		24,933		39,999
Other		28,070		38,362
Gross deferred tax assets	$	212,235	$	299,319
Valuation allowance		(82,825)		(83,704)
Total deferred tax assets	$	129,410	$	215,615
Deferred tax liabilities:
Plant and equipment		1,075		1,245
Convertible Notes		—		75
Other		4,311		4,825
Total deferred tax liabilities	$	5,386	$	6,145
Net deferred tax asset	$	124,024	$	209,470

The Company provides for deferred income taxes for temporary differences arising from differences between the financial statement and tax basis of assets and liabilities existing at each balance sheet date using enacted tax rates expected to be in effect when the related taxes are expected to be paid or recovered.

The Company assesses the need for a valuation allowance against its deferred tax assets (including temporary differences and tax attributes) through a review of all available positive and negative evidence. On the basis of this assessment for the year ended December 31, 2022, the Company determined that it is more likely than not that the net deferred tax assets would be realized, except for certain state NOLs and capital loss carryforwards, and released the valuation allowance that was recorded against the Company's net deferred tax assets. As of December 31, 2023, the Company continues to carry a valuation allowance against certain state NOLs and capital loss carryforwards.

At December 31, 2023, the Company has gross NOL carryforwards for federal income tax purposes of $319.3 million. Of these carryforwards, approximately $46.6 million will expire, if not utilized, starting in 2037. The remaining carryforwards have no expiration, however, they can only be used to offset 80% of U.S. federal taxable income.

The ability to use the NOLs in existence immediately prior to emergence from bankruptcy in 2016 has been limited by the “ownership change” under Section 382 of the Internal Revenue Code (the “Code”) that occurred as a result of such emergence (the “Emergence Ownership Change”). NOLs generated after the Emergence Ownership Change are generally not subject to limitations resulting from the Emergence Ownership Change.

On August 16, 2022, the Inflation Reduction Act of 2022 (“IRA”) was signed into law. This legislation introduces a 15% corporate alternative minimum tax among its key tax provisions. The IRA is effective for years beginning after December 31, 2022. The Company did not experience any related material impact in the current year. The Company will continue to evaluate the effects of IRA on future periods, however, does not anticipate any material impact.

A reconciliation of the beginning and ending amounts of gross unrecognized tax benefits follows:


	(In thousands)
Balance at December 31, 2020	$	48,116
Additions based on tax positions to the current year		3,467
Additions for tax positions related to the prior year		3,931
Reductions for tax positions of prior years		(2,868)
Reductions as a result of lapses in the statute of limitations		(3,683)
Balance at December 31, 2021		48,963
Additions for tax positions related to the current year		5,446
Additions for tax positions related to the prior year		768
Reductions for tax positions of prior years		(125)
Reductions as a result of lapses in the statute of limitations		(36,988)
Balance at December 31, 2022		18,064
Additions based on tax positions related to the current year		3,019
Additions for tax positions related to the prior year		731
Increases for tax positions of prior years		1,485
Reductions as a result of lapses in the statute of limitations		(2,732)
Balance at December 31, 2023	$	20,567

If recognized, the entire amount of the gross unrecognized tax benefits at December 31, 2023 would affect the effective tax rate. The Company recognizes interest and penalties related to unrecognized tax benefits in income tax expense. The Company had no accrued interest and penalties at December 31, 2023 and 2022, respectively. In the next 12 months, no gross unrecognized tax benefits are expected to be reduced due to the expiration of the statute of limitations.

The Company is subject to U.S. federal income tax as well as income tax in multiple state jurisdictions. The tax years 2016 through 2022 remain open to examination for U.S. federal income tax matters and 2002 through 2022 remain open to examination for various state income tax matters.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Revenue Recognition (Details) - Coal T in Millions	Dec. 31, 2023 T
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation (in tons)	59.3
Remaining performance obligations, fixed price contracts (in tons)	54.3
Remaining performance obligation, variable price contracts (in tons)	5.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation (in tons)	59.7
Remaining performance obligations, fixed price contracts (in tons)	58.9
Remaining performance obligation, variable price contracts (in tons)	0.8

Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Final contribution to the plan, cost	$ 3,200
Health care cost trend rate assumed	7.37%
Ultimate trend rate	4.00%
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation of pension plans	$ 1,000	$ 122,400
Weighted-average interest credit rate (as percent)		4.25%
Other postretirement benefits payments	20,500	$ 18,700	$ 16,800
Pension plan assets	0	121,127	177,499
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Discount rate increased plan obligations	(1,000)
Health care cost trend assumption	(1,400)
Claims cost assumption	(900)
Pension plan assets	$ 0	$ 0	$ 0

Leases - Future minimum lease payments (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Operating Leases
2024	$ 3,281
2025	3,266
2026	3,080
2027	1,533
Total minimum lease payments	11,160
Less imputed interest	(1,020)
Total operating lease liabilities	10,140
Finance Leases
2024	1,210
2025	2,111
Total minimum lease payments	3,321
Less imputed interest	(201)
Total finance lease liabilities	$ 3,120

Equity Method Investments and Membership Interests in Joint Ventures

12 Months Ended

Dec. 31, 2023

Equity Method Investments and Membership Interests in Joint Ventures

Equity Method Investments and Membership Interests in Joint Ventures

7. Equity Method Investments and Membership Interests in Joint Ventures

The Company accounts for its investments and membership interests in joint ventures under the equity method of accounting if the Company has the ability to exercise significant influence, but not control, over the entity. Equity method investments are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the investments may not be recoverable.

Below are the equity method investments reflected in the consolidated balance sheets:



(In thousands)	DTA

December 31, 2021	$	15,403
Advances to affiliates, net		9,575
Equity in comprehensive loss		(7,711)
December 31, 2022	$	17,267
Advances to affiliates, net		17,345
Equity in comprehensive loss		(11,797)

December 31, 2023	$	22,815

The Company holds a 35% general partnership interest in Dominion Terminal Associates LLP (“DTA”), which is accounted for under the equity method. DTA operates a ground storage-to-vessel coal transloading facility in Newport News, Virginia for use by the partners. Under the terms of a throughput and handling agreement with DTA, each partner is charged its share of cash operating and debt-service costs in exchange for the right to use the facility’s loading capacity and is required to make periodic cash advances to DTA to fund such costs.

The Company is not required to make any future contingent payments related to development financing for its equity investee.

Consolidated Income Statements - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Consolidated Income Statements
Revenues	$ 3,145,843	$ 3,724,593	$ 2,208,042
Costs, expenses and other operating
Cost of sales (exclusive of items shown separately below)	2,341,956	2,338,863	1,579,836
Depreciation, depletion and amortization	146,418	133,300	120,327
Accretion on asset retirement obligations	21,170	17,721	21,748
Change in fair value of coal derivatives, net	1,572	1,274	(2,392)
Selling, general and administrative expenses	98,871	105,355	92,342
Loss on divestitures			24,225
Other operating (income) expense, net	(10,598)	18,669	4,826
Costs, expenses and other operating	2,599,389	2,615,182	1,840,912
Income from operations	546,454	1,109,411	367,130
Interest income (expense), net
Interest expense	(14,821)	(20,461)	(23,972)
Interest and investment income	17,259	7,299	628
Interest income (expense), net	2,438	(13,162)	(23,344)
Income before nonoperating expenses	548,892	1,096,249	343,786
Nonoperating expense
Non-service related pension and postretirement benefit credits (costs)	3,786	(2,841)	(4,339)
Net loss resulting from early retirement of debt	(1,126)	(14,420)
Nonoperating expenses	2,660	(17,261)	(4,339)
Income before income taxes	551,552	1,078,988	339,447
Provision for (benefit from) income taxes	87,514	(251,926)	1,874
Net income	$ 464,038	$ 1,330,914	$ 337,573
Net income per common share
Basic earnings per share (in dollars per share)	$ 25.45	$ 77.67	$ 22.04
Diluted earnings per share (in dollars per share)	$ 24.20	$ 63.88	$ 19.20
Weighted average shares outstanding
Basic weighted average shares outstanding (in shares)	18,233	17,136	15,318
Diluted weighted average shares outstanding (in shares)	19,183	20,985	17,579
Dividends declared per common share (in dollars per share)	$ 10.66	$ 25.11

Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Taxes (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2024	Dec. 31, 2020
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 82,825	$ 83,704
Pre-tax profit	551,552	1,078,988	$ 339,447
NOL carryforwards for federal income tax purposes	319,300
Operating loss carryforwards subject to expiration	$ 46,600
NOL carryforwards offset percentage	80.00%
Interest and penalties accrued related to unrecognized tax benefits	$ 0
Gross unrecognized tax benefits	$ 20,567	$ 18,064	$ 48,963		$ 48,116
Forecast
Operating Loss Carryforwards [Line Items]
Gross unrecognized tax benefits				$ 0

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(11))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-30

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479557/942-235-S99-1

Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-SubTopic 20
-Topic 940
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481913/940-20-25-1

Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

+ Details

Risk Concentrations (Tables)

12 Months Ended

Dec. 31, 2023

Risk Concentrations

Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas


	Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,
	2023		2022		2021
(In thousands)
Europe	$	696,975	$	939,955	$	592,702
Asia		935,158		1,210,855		446,724
Central and South America		136,423		160,642		109,613
Africa		4,971		—		—
Total	$	1,773,527	$	2,311,452	$	1,149,039

Divestitures (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
Divestitures (Details) - USD ($) $ in Thousands	Nov. 30, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on divestitures			$ 24,225
Knight Hawk \| Knight Hawk \| Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Percentage of ownership interest	49.50%
Notes receivable term		3 years
Notes receivable periodic payment receivable		$ 500	500
Notes Receivable, Related Parties		18,000	18,000
Consideration for sale		$ 20,000	38,000
Loss on divestitures			$ 24,200
DTA
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership interest				35.00%

Segment Information - Reconciliation segment income to net income (loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Information
Net Income (Loss)	$ 464,038	$ 1,330,914	$ 337,573
Provision for (benefit from) income taxes	87,514	(251,926)	1,874
Interest expense, net	(2,438)	13,162	23,344
Depreciation, depletion and amortization	146,418	133,300	120,327
Accretion on asset retirement obligation	21,170	17,721	21,748
Loss on divestitures			24,225
Non-service related pension and postretirement benefit (credits) costs	(3,786)	2,841	4,339
Net loss resulting from early retirement of debt	1,126	14,420
Adjusted EBITDA	714,042	1,260,432	533,430
EBITDA from idled or otherwise disposed operations	15,986	(828)	2,469
Selling, general and administrative expenses	98,871	105,355	92,342
Other	14,404	10,857	(9,702)
Segment Adjusted EBITDA from coal operations	$ 843,303	$ 1,375,816	$ 618,539

Asset Retirement Obligations (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
asset retirement obligations [Line Items]
Surety bonds outstanding	$ 552,500
Cash collateral for surety bond	5,600
Sinking fund for asset retirement obligations	6,273	$ 115,993	$ 20,000
Asset retirement obligations
asset retirement obligations [Line Items]
Surety bonds outstanding	455,700
Cash collateral for surety bond	600
Sinking fund for asset retirement obligations	$ 142,300

Workers Compensation Expense (Tables)

12 Months Ended

Dec. 31, 2023

Workers Compensation Expense

Workers' compensation expense

Workers’ compensation expense consists of the following components:


	Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,
	2023		2022		2021

Self-insured occupational disease benefits:
Service cost	$	3,974	$	5,991	$	7,796
Interest cost⁽¹⁾		6,041		4,610		4,439
Net amortization⁽¹⁾		(965)		628		2,363
Total occupational disease	$	9,050	$	11,229	$	14,598
Traumatic injury claims and assessments		277		(3,783)		3,925
Total workers’ compensation expense	$	9,327	$	7,446	$	18,523

(1)

Schedule of Changes in Occupational Disease Obligations


	Year Ended		Year Ended
	December 31,		December 31,
(In thousands)	2023		2022
Beginning of period	$	120,008	$	167,585
Service cost		3,974		5,991
Interest cost		6,041		4,610
Actuarial loss (gain)		10,721		(48,859)
Benefit and administrative payments		(11,526)		(9,319)
	$	129,218	$	120,008

Schedule of Occupational Disease Obligation Assumptions Used


	Year Ended December 31, 2023	Year Ended December 31, 2022
(Percentages)
Discount rate	5.01	5.21

Workers' compensation liabilities


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
(In thousands)
Occupational disease costs	$	129,218	$	120,008
Traumatic and other workers’ compensation claims		44,156		53,332
Total obligations		173,374		173,340
Less amount included in accrued expenses		18,724		17,584
Noncurrent obligations	$	154,650	$	155,756

Schedule of expected future payments



Year	(In thousands)
2024	$	12,837
2025		13,634
2026		13,750
2027		14,186
2028		14,564
Next 5 years		79,731
	$	148,702

Divestitures

12 Months Ended

Dec. 31, 2023

Divestitures

Divestitures

4. Divestitures

In November 2021, the Company sold its 49.5% ownership in Knight Hawk Holdings, LLC (Knight Hawk”) to CBR, LLC. The Company received total proceeds of $38 million which consisted of $20 million received in the fourth quarter of 2021 and a three year note receivable for $18 million with monthly payments of $0.5 million. The sale resulted in a non-cash loss of $24.2 million that was recorded in “Loss on divestitures” in the year ended December 31, 2021.

Basis of Presentation

12 Months Ended

Dec. 31, 2023

Basis of Presentation

Basis of Presentation

1. Basis of Presentation

The accompanying consolidated financial statements include the accounts of Arch Resources, Inc. (“Arch Resources”) and its subsidiaries and controlled entities (the “Company”). Unless the context indicates otherwise, the terms “Arch” and the “Company” are used interchangeably in this Annual Report on Form 10-K. The Company’s primary business is the production of metallurgical and thermal coal from underground and surface mines located throughout the United States, for sale to steel producers, utility companies, and industrial accounts both in the United States and around the world. The Company currently operates mining complexes in West Virginia, Wyoming and Colorado. All subsidiaries are wholly-owned. Intercompany transactions and accounts have been eliminated in consolidation.

Asset Retirement Obligations (Rollforward) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at beginning of period (including current portion)	$ 244,368	$ 214,453
Accretion expense	21,170	17,721	$ 21,748
Adjustments to the liability from changes in estimates	17,747	25,914
Reclamation work completed	(21,456)	(13,720)
Balance at period end	261,829	244,368	$ 214,453
Current portion included in accrued expenses	(6,089)	(8,632)
Noncurrent liability	$ 255,740	$ 235,736

Fair Value Measurements

12 Months Ended

Dec. 31, 2023

Fair Value Measurements

Fair Value Measurements

13. Fair Value Measurements

The hierarchy of fair value measurements assigns a level to fair value measurements based on the inputs used in the respective valuation techniques. The levels of the hierarchy, as defined below, give the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs.

● Level 1 is defined as observable inputs such as quoted prices in active markets for identical assets. Level 1 assets include U.S. Treasury securities, and coal swaps and futures that are submitted for clearing on the New York Mercantile Exchange.

● Level 2 is defined as observable inputs other than Level 1 prices. These include quoted prices for similar assets or liabilities in an active market, quoted prices for identical assets and liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. The Company’s Level 2 assets and liabilities include U.S. government agency securities, coal commodity contracts and interest rate swaps with fair values derived from quoted prices in over-the-counter markets or from prices received from direct broker quotes.

● Level 3 is defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. These include the Company’s commodity option contracts (heating oil) valued using modeling techniques, such as Black-Scholes, that require the use of inputs, particularly volatility, that are rarely observable. Changes in the unobservable inputs would not have had a significant impact on the reported Level 3 fair values at December 31, 2023 and 2022.

The table below sets forth, by level, the Company’s financial assets and liabilities that are recorded at fair value in the accompanying consolidated balance sheet:


	December 31, 2023
	Total		Level 1		Level 2		Level 3

	(In thousands)
Assets:
Investments in marketable securities	$	32,724	$	28,773	$	3,951	$	—
Derivatives		998		—		—		998
Fund for asset retirement obligations		142,266		142,266		—		—
Total assets	$	175,988	$	171,039	$	3,951	$	998
Liabilities:
Derivatives	$	165	$	—	$	165	$	—


	Fair Value at December 31, 2022
	Total		Level 1		Level 2		Level 3

	(In thousands)
Assets:
Investments in marketable securities	$	36,993	$	28,301	$	8,692	$	—
Derivatives		3,955		—		2,655		1,300
Fund for asset retirement obligations		135,993		135,993		—		—
Total assets	$	176,941	$	164,294	$	11,347	$	1,300
Liabilities:
Derivatives	$	—	$	—	$	—	$	—

The Company’s contracts with its counterparties allow for the settlement of contracts in an asset position with contracts in a liability position in the event of default or termination. For classification purposes, the Company records the net fair value of all the positions with these counterparties as a net asset or liability. Each level in the table above displays the underlying contracts according to their classification in the accompanying Consolidated Balance Sheet, based on this counterparty netting.

The following table summarizes the change in the fair values of financial instruments categorized as Level 3.


	2023		2022
(In thousands)
Balance, beginning of period	$	1,300	$	1,219
Realized and unrealized gains (losses) recognized in earnings, net		(4,192)		7,019
Purchases		5,400		4,673
Settlements		(1,510)		(11,611)
Ending balance	$	998	$	1,300

Net unrealized losses of $2.6 million were recognized during the year ended December 31, 2023 related to Level 3 financial instruments held on December 31, 2023.

Cash and Cash Equivalents

At December 31, 2023 and 2022, the carrying amounts of cash and cash equivalents approximate their fair value.

Fair Value of Long-Term Debt

At December 31, 2023 and 2022, the fair value of the Company’s debt, including amounts classified as current, was $142.1 million and $223.0 million, respectively. Fair values are based upon observed prices in an active market, when available, or from valuation models using market information, which fall into Level 2 in the fair value hierarchy.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Capital Stock (Tables)

12 Months Ended

Dec. 31, 2023

Capital Stock

Dividends declared and paid


2023:	Dividends per share		Amount (in thousands)
1st quarter	$	3.11	$	66,902
2nd quarter		2.45		45,011
3rd quarter		3.97		71,877
4th quarter		1.13		22,335
Total cash dividends declared and paid	$	10.66	$	206,125


			Amount
2022:	Dividends per share		(in thousands)
1st quarter	$	0.25	$	3,851
2nd quarter		8.11		150,716
3rd quarter		6.00		110,071
4th quarter		10.75		191,754
Total cash dividends declared and paid	$	25.11	$	456,392

Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2023

Employee Benefit Plans

Schedule of Pension Benefit Costs (Credits)


	Pension Benefits				Other Postretirement Benefits
	Year Ended		Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,		December 31,
	2023		2022		2023		2022
(In thousands)
CHANGE IN BENEFIT OBLIGATIONS
Benefit obligations at beginning of period	$	122,430	$	169,976	$	54,514	$	79,245
Service cost		—		—		231		282
Interest cost		4,108		5,264		2,694		2,006
Settlement gain		(1,586)		(771)		—		—
Plan Settlements		(124,382)		—		—		—
Benefits paid		(4,652)		(22,164)		(3,858)		(4,834)
Other-primarily actuarial gain		5,070		(29,875)		(2,227)		(22,185)
Benefit obligations at end of period	$	988	$	122,430	$	51,354	$	54,514
CHANGE IN PLAN ASSETS
Value of plan assets at beginning of period	$	121,127	$	177,499	$	—	$	—
Actual return on plan assets		4,625		(34,325)		—		—
Employer contributions		3,282		117		3,858		4,834
Plan Settlements		(124,382)		—		—		—
Benefits paid		(4,652)		(22,164)		(3,858)		(4,834)
Value of plan assets at end of period	$	—	$	121,127	$	—	$	—
Accrued benefit net obligation	$	(988)	$	(1,303)	$	(51,354)	$	(54,514)
ITEMS NOT YET RECOGNIZED AS A COMPONENT OF NET PERIODIC BENEFIT COST
Prior service credit	$	—	$	945	$	—	$	—
Accumulated gain		1,150		5,164		32,871		40,334
	$	1,150	$	6,109		32,871	$	40,334
BALANCE SHEET AMOUNTS
Noncurrent asset	$	—	$	—	$	—	$	—
Current liability		(110)		(202)		(3,860)		(4,840)
Noncurrent liability		(878)		(1,101)		(47,494)		(49,674)
	$	(988)	$	(1,303)	$	(51,354)	$	(54,514)

Schedule of Other Postretirement Benefit Costs


	Pension Benefits						Other Postretirement Benefits
	Year Ended		Year Ended		Year Ended		Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,		December 31,		December 31,		December 31,
	2023		2022		2021		2023		2022		2021
(In thousands)
Service cost	$	—	$	—	$	—	$	231	$	282	$	341
Interest cost⁽¹⁾		4,108		5,264		4,334		2,694		2,006		2,113
Settlements/Terminations⁽¹⁾		(1,586)		(771)		(1,768)		—		—		—
Expected return on plan assets⁽¹⁾		(4,048)		(6,173)		(7,245)		—		—		—
Amortization of prior service credits⁽¹⁾		(98)		(147)		(128)		—		—		—
Amortization of other actuarial losses (gains) ⁽¹⁾		(553)		(313)		(62)		(9,690)		(2,508)		—
Net benefit cost (credit)	$	(2,177)	$	(2,140)	$	(4,869)	$	(6,765)	$	(220)	$	2,454

(1)

Schedule of Assumptions Used


	Year Ended	Year Ended
	December 31,	December 31,
	2023	2022
(Percentages)
Pension Benefits
Discount rate	4.89	5.20/5.15

Other Postretirement Benefits
Discount rate	4.94	5.19


	Year Ended	Year Ended	Year Ended
	December 31,	December 31,	December 31,
	2023	2022	2021
(Percentages)
Pension Benefits
Discount rate	5.20	4.47	2.50
Expected return on plan assets	4.20	4.06	4.30

Other Postretirement Benefits
Discount rate	5.19	2.63	2.17

Schedule of Allocation of Plan Assets


	Total				Level 1				Level 2				Level 3
	2023		2022		2023		2022		2023		2022		2023		2022

	(In thousands)
Fixed income securities:
U.S. government securities^(A)	$	—	$	37,148	$	—	$	34,143	$	—	$	3,005	$	—	$	—
Non-U.S. government securities^(B)		—		2,340		—		—		—		2,340		—		—
Corporate fixed income^(C)		—		41,286		—		—		—		41,286		—		—
State and local government securities^(D)		—		2,504		—		—		—		2,504		—		—
Other investments^(E)		—		15,616		—		—		—		15,616		—		—
Total	$	—	$	98,894	$	—	$	34,143	$	—	$	64,751	$	—	$	—
Assets at net asset value^(F)		—		22,233
	$	—	$	121,127

(A)

U.S. government securities includes agency and treasury debt. These investments are valued using dealer quotes in an active market.

(B)

(C)

(D)

(E)

(F)

Schedule of Expected Benefit Payments


			Other
	Pension		Postretirement
	Benefits		Benefits

	(In thousands)
2024	$	109	$	4,699
2025		106		4,645
2026		103		4,564
2027		99		4,493
2028		95		4,381
Next 5 years		393		19,208
	$	905	$	41,990

Taxes (Schedule of Components of Income Tax) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
Federal	$ 106	$ (30,107)	$ 1,525
State	317	204	342
Total current	423	(29,903)	1,867
Deferred:
Federal	85,002	(209,130)	7
State	2,089	(12,893)
Total deferred	87,091	(222,023)	7
Provision for (benefit from) income taxes	$ 87,514	$ (251,926)	$ 1,874

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Employee Benefit Plans (Schedule of Assumptions Used to Calculate Benefit Obligations) (Details)	Dec. 31, 2023	Dec. 31, 2022
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	4.89%
Pension Benefits \| Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate		5.15%
Pension Benefits \| Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate		5.20%
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate	4.94%	5.19%

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Paid-in Capital	Treasury Stock, at cost	Retained Earnings	Accumulated Other Comprehensive Income	Total
Beginning Balance at Dec. 31, 2020	$ 253	$ 767,484	$ (827,381)	$ 378,906	$ (35,701)	$ 283,561
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends on common shares				(4,001)		(4,001)
Issuance of shares of common stock under long-term incentive plan	2					2
Employee stock-based compensation		20,539				20,539
Common stock withheld related to net share settlement of equity awards		(4,842)				(4,842)
Warrants exercised		1,175				1,175
Total comprehensive income (loss)				337,573	49,859	387,432
Ending Balance at Dec. 31, 2021	255	784,356	(827,381)	712,478	14,158	683,866
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of accounting change on convertible debt		(39,239)		6,718		(32,521)
Dividends on common shares				(456,459)		(456,459)
Dividend Equivalents earned on RSU grants		826		(28,277)		(27,451)
Purchase of common stock under share repurchase program			(158,790)			(158,790)
Cash paid for convertible debt repurchased		(61,124)				(61,124)
Issuance of shares of common stock under long-term incentive plan	1					1
Employee stock-based compensation		27,383				27,383
Issuance of shares of common stock for convertible debt exchanged	26	(32)				(6)
Common stock withheld related to net share settlement of equity awards		(7,052)				(7,052)
Warrants exercised	6	19,542				19,548
Total comprehensive income (loss)				1,330,914	47,271	1,378,185
Ending Balance at Dec. 31, 2022	288	724,660	(986,171)	1,565,374	61,429	1,365,580
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends on common shares				(192,471)		(192,471)
Dividend Equivalents earned on RSU grants		428		(6,923)		(6,495)
Purchase of common stock under share repurchase program			(123,508)			(123,508)
Cash paid for convertible debt repurchased		(44,486)				(44,486)
Issuance of shares of common stock under long-term incentive plan	3	(3)
Employee stock-based compensation		25,443				25,443
Common stock withheld related to net share settlement of equity awards		(30,240)				(30,240)
Warrants exercised	15	44,227				44,242
Total comprehensive income (loss)				464,038	(22,647)	441,391
Ending Balance at Dec. 31, 2023	$ 306	$ 720,029	$ (1,109,679)	$ 1,830,018	$ 38,782	$ 1,479,456

Leases - Lease assets and liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets
Operating lease right-of-use assets	$ 9,626	$ 12,106
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent	Other Assets, Noncurrent
Financing lease right-of-use assets	$ 1,621	$ 2,918
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent	Other Assets, Noncurrent
Total Lease Assets	$ 11,247	$ 15,024
Liabilities
Financing lease liabilities - current	$ 1,041	$ 977
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued Liabilities, Current	Accrued Liabilities, Current
Operating lease liabilities - current	$ 2,789	$ 2,722
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued Liabilities, Current	Accrued Liabilities, Current
Financing lease liabilities - long-term	$ 2,079	$ 3,121
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Operating lease liabilities - long-term	$ 7,351	$ 9,993
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Total Lease Liabilities	$ 13,260	$ 16,813

Segment Information

12 Months Ended

Dec. 31, 2023

Segment Information

Segment Information

23. Segment Information

The Company’s reportable business segments are based on two distinct lines of business, metallurgical and thermal, and may include a number of mine complexes. The Company manages its coal sales by market and coal quality, not by individual mining complex. Geology, coal transportation routes to customers, and regulatory environments also have a significant impact on the Company’s marketing and operations management. Mining operations are evaluated based on Adjusted EBITDA, per-ton cash operating costs (defined as including all mining costs except depreciation, depletion, amortization, accretion on asset retirement obligations, and pass-through transportation expenses, divided by segment tons sold), and on other non-financial measures, such as safety and environmental performance. Adjusted EBITDA is not a measure of financial performance in accordance with generally accepted accounting principles, and items excluded from Adjusted EBITDA are significant in understanding and assessing the Company’s financial condition. Therefore, Adjusted EBITDA should not be considered in isolation, nor as an alternative to net income (loss), income (loss) from operations, cash flows from operations or as a measure of our profitability, liquidity or performance under generally accepted accounting principles. The Company uses Adjusted EBITDA to measure the operating performance of its segments and allocate resources to the segments. Furthermore, analogous measures are used by industry analysts and investors to evaluate the Company’s operating performance. Investors should be aware that the Company’s presentation of Adjusted EBITDA may not be comparable to similarly titled measures used by other companies. The Company reports its results of operations primarily through the following reportable segments: Metallurgical (MET) segment, containing the Company’s metallurgical operations in West Virginia, and the Thermal segment containing the Company’s thermal operations in Wyoming and Colorado.

In November of 2021, the Company sold its equity investment Knight Hawk Holdings, LLC, which had been part of its Corporate, Other and Eliminations grouping. For further information on the sale of Knight Hawk Holdings, LLC, please see Note 4, “Divestitures” to the Consolidated Financial Statements.

Reporting segment results for the years ended December 31, 2023, 2022 and 2021 are presented below. The Corporate, Other, and Eliminations grouping includes these charges: idle operations; change in fair value of coal

derivatives, net; corporate overhead; land management activities; other support functions; and the elimination of intercompany transactions.


					Corporate,
					Other and
(In thousands)	MET		Thermal		Eliminations		Consolidated

Year Ended December 31, 2023
Revenues	$	1,892,326	$	1,253,517	$	—	$	3,145,843
Adjusted EBITDA		717,834		125,469		(129,261)		714,042
Depreciation, depletion and amortization		116,550		28,996		872		146,418
Accretion on asset retirement obligation		2,507		17,255		1,408		21,170
Total assets		1,064,510		437,776		981,887		2,484,173
Capital expenditures		141,210		33,212		1,615		176,037

Year Ended December 31, 2022
Revenues	$	2,157,710	$	1,566,883	$	—	$	3,724,593
Adjusted EBITDA		1,021,932		353,884		(115,384)		1,260,432
Depreciation, depletion and amortization		111,772		20,650		878		133,300
Accretion on asset retirement obligation		2,213		13,775		1,733		17,721
Total assets		1,058,217		381,099		993,792		2,433,108
Capital expenditures		140,031		28,578		4,119		172,728

Year Ended December 31, 2021
Revenues	$	1,149,133	$	1,057,480	$	1,429	$	2,208,042
Adjusted EBITDA		442,830		175,709		(85,109)		533,430
Depreciation, depletion and amortization		99,171		20,231		925		120,327
Accretion on asset retirement obligation		2,030		17,675		2,043		21,748
Total assets		964,761		205,147		947,252		2,117,160
Capital expenditures		227,802		5,949		11,689		245,440

A reconciliation of segment Adjusted EBITDA to net income:


	Year Ended		Year Ended		Year Ended
	December 31,		December 31,		December 31,
(In thousands)	2023		2022		2021
Net income	$	464,038	$	1,330,914	$	337,573
Provision for (benefit from) income taxes		87,514		(251,926)		1,874
Interest (income) expense, net		(2,438)		13,162		23,344
Depreciation, depletion and amortization		146,418		133,300		120,327
Accretion on asset retirement obligations		21,170		17,721		21,748
Loss on divestitures		—		—		24,225
Non-service related pension and postretirement benefit (credits) costs		(3,786)		2,841		4,339
Net loss resulting from early retirement of debt		1,126		14,420		—
Adjusted EBITDA	$	714,042	$	1,260,432	$	533,430
EBITDA from idled or otherwise disposed operations		15,986		(828)		2,469
Selling, general and administrative expenses		98,871		105,355		92,342
Other		14,404		10,857		(9,702)
Segment Adjusted EBITDA from coal operations	$	843,303	$	1,375,816	$	618,539

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-15

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//280/tableOfContent

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-26

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-34

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

+ Details

Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts receivable and other receivables
Reserves deducted from asset accounts:
Balance at Beginning of Year	$ 10,636	$ 10,636	$ 10,636
Additions (Reductions) Charged to Costs and Expenses	(2,200)
Deductions	8,436
Balance at End of Year	0	10,636	10,636
Current assets - supplies and inventory
Reserves deducted from asset accounts:
Balance at Beginning of Year	2,439	2,249	574
Additions (Reductions) Charged to Costs and Expenses	522	314	1,860
Deductions	1,365	124	185
Balance at End of Year	1,596	2,439	2,249
Deferred income taxes
Reserves deducted from asset accounts:
Balance at Beginning of Year	83,704	504,392	573,995
Additions (Reductions) Charged to Costs and Expenses	(879)	(420,688)	(69,603)
Charged to Other Accounts
Balance at End of Year	$ 82,825	$ 83,704	$ 504,392

Equity Method Investments and Membership Interests in Joint Ventures (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Nov. 30, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
Non-cash loss on sale of equity method investments			$ (24,225)
Knight Hawk \| Knight Hawk \| Sale
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest	49.50%
Consideration for sale		$ 20,000	38,000
Notes receivable term		3 years
Note receivable		$ 18,000	18,000
Notes receivable periodic payment receivable		$ 500	500
Non-cash loss on sale of equity method investments			$ (24,200)
DTA
Schedule of Equity Method Investments [Line Items]
Ownership interest				35.00%

Leases - Other information related to leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Lease information:
Operating lease cost	$ 3,263	$ 3,323
Operating cash flows from operating leases	3,356	3,389
Financing lease cost	1,572	1,572
Operating cash flows from financing leases	$ 1,210	$ 1,210

Investments in Available-for-Sale Securities - Schedule of investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Cost Basis	$ 32,715	$ 37,014
Available-for-sale, Gross Unrealized Gains	15	21
Available-for-sale, Gross Unrealized Losses	(6)	(42)
Available-for-sale, Fair Value	32,724	36,993
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Cost Basis	28,764	28,325
Available-for-sale, Gross Unrealized Gains	14	1
Available-for-sale, Gross Unrealized Losses	(5)	(25)
Available-for-sale, Fair Value	28,773	28,301
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Cost Basis	3,951	8,689
Available-for-sale, Gross Unrealized Gains	1	20
Available-for-sale, Gross Unrealized Losses	(1)	(17)
Available-for-sale, Fair Value	$ 3,951	$ 8,692

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

+ Details

Asset Retirement Obligations

12 Months Ended

Dec. 31, 2023

Asset Retirement Obligation

Asset Retirement Obligations

12. Asset Retirement Obligations

The Company’s asset retirement obligations arise from the Federal Surface Mining Control and Reclamation Act of 1977 and similar state statutes, which require that mine property be restored in accordance with specified standards and an approved reclamation plan. The required reclamation activities to be performed are outlined in the Company’s mining permits. These activities include reclaiming the pit and support acreage at surface mines, sealing portals at underground mines, reclaiming refuse areas and slurry ponds and water treatment.

The following table describes the changes to the Company’s asset retirement obligation liability:


	Year Ended		Year Ended
	December 31,		December 31,
	2023		2022
(In thousands)
Balance at beginning of period (including current portion)	$	244,368	$	214,453
Accretion expense		21,170		17,721
Adjustments to the liability from changes in estimates		17,747		25,914
Reclamation work completed		(21,456)		(13,720)
Balance at period end	$	261,829	$	244,368
Current portion included in accrued expenses		(6,089)		(8,632)
Noncurrent liability	$	255,740	$	235,736

As of December 31, 2023, the Company had $455.7 million in reclamation surety bonds outstanding and posted $0.6 million in cash as collateral; this amount is recorded within “Noncurrent assets” on the Consolidated Balance Sheets. Additionally, through December 31, 2023, the Company has contributed $142.3 million to a fund that will serve to defease the long-term asset retirement obligation for its thermal asset base; this amount is recorded as “Fund for asset retirement obligations” on the Consolidated Balance Sheets.

Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Inventories
Coal	$ 99,174	$ 96,954
Repair parts and supplies	145,087	126,061
Inventories	244,261	223,015
Allowance for slow-moving and obsolete inventories	$ 1,600	$ 2,400

Derivatives (Tables)

12 Months Ended

Dec. 31, 2023

Derivatives

Disclosure of Fair Value of Derivatives


	December 31, 2023						December 31, 2022
Fair Value of Derivatives	Asset		Liability				Asset		Liability
(In thousands)	Derivative		Derivative				Derivative		Derivative
Derivatives Not Designated as Hedging Instruments
Heating oil -- diesel purchases		998		—				1,300		—
Coal -- risk management		—		(165)				1,407		—
Total	$	998	$	(165)			$	2,707	$	—
Total derivatives	$	998	$	(165)			$	2,707	$	—
Effect of counterparty netting		—		—				—		—
Net derivatives as classified in the balance sheets	$	998	$	(165)	$	833	$	2,707	$	—	$	2,707


Fair Value of Derivatives		December 31,		December 31,
(In thousands)		2023		2022
Net derivatives as reflected on the balance sheets (in thousands)
Heating Oil and coal	Other current assets	$	998	$	2,707
Coal	Accrued expenses and other current liabilities		(165)		—
		$	833	$	2,707

Effects of Derivatives on Measures of Financial Performance

Derivatives Not Designated as Hedging Instruments (in thousands)

For the noted periods,


		Gain (Loss) Recognized
		Year Ended		Year Ended		Year Ended
		December 31,		December 31,		December 31,
		2023		2022		2021
Coal trading— realized and unrealized	⁽³⁾	$	—	$	—	$	—
Coal risk management— unrealized	⁽³⁾		(1,572)		(1,274)		2,392
Natural gas trading — realized and unrealized	⁽³⁾		—		—		—
Change in fair value of coal derivatives and coal trading activities, net total		$	(1,572)	$	(1,274)	$	2,392

Coal risk management — realized	⁽⁴⁾	$	6,254	$	(42,068)	$	(27,464)
Heating oil — diesel purchases	⁽⁴⁾	$	(4,079)	$	8,309	$	—

Location in Consolidated Statements of Operations:

(1)

— Revenues

(2)

— Cost of sales

(3)

— Change in fair value of coal derivatives, net

(4)

— Other operating income, net

Derivatives (Details) - Not Designated as Hedging Instrument gal in Millions	12 Months Ended
	Dec. 31, 2023 $ / Option gal
Call Option \| Heating Oil
Derivative [Line Items]
Quantities under derivative contracts (in gallons)	24
Derivative, average price risk option strike price (in used per gallon) \| $ / Option	2.96
Diesel Purchases \| Minimum
Derivative [Line Items]
Diesel fuel purchased annually (in gallons)	30
Diesel Purchases \| Maximum
Derivative [Line Items]
Diesel fuel purchased annually (in gallons)	35

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued Expenses and Other Current Liabilities.
Payroll and employee benefits	$ 37,259	$ 61,836
Taxes other than income taxes	51,155	53,105
Interest	2,395	2,511
Workers' compensation	18,724	17,584
Asset retirement obligations	6,089	8,632
Other	11,995	13,375
Accrued expenses and other current liabilities	$ 127,617	$ 157,043

Investments in Available-for-Sale Securities (Tables)

12 Months Ended

Dec. 31, 2023

Investments in Available-for-Sale Securities

Available-for-sale Securities


	December 31, 2023

			Gross					Allowance
			Unrealized					for - Credit	Fair
	Cost Basis		Gains		Losses			Losses	Value

	(In thousands)
Available-for-sale:
U.S. government and agency securities	$	28,764	$	14	$	(5)	$	—	$	28,773
Corporate notes and bonds		3,951		1		(1)		—		3,951
Total Investments	$	32,715	$	15	$	(6)	$	—	$	32,724


	December 31, 2022

			Gross					Allowance
			Unrealized					for - Credit	Fair
	Cost Basis		Gains			Losses		Losses	Value

	(In thousands)
Available-for-sale:
U.S. government and agency securities	$	28,325	$	1	$	(25)	$	—	$	28,301
Corporate notes and bonds		8,689		20		(17)		—		8,692
Total Investments	$	37,014	$	21	$	(42)	$	—	$	36,993

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

+ Details

Employee Benefit Plans (Summary of Estimated Future Benefit Payments) (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
2024	$ 109
2025	106
2026	103
2027	99
2028	95
Next 5 years	393
Defined Benefit Plan, Expected Future Benefit Payments Total	905
Total	905
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
2024	4,699
2025	4,645
2026	4,564
2027	4,493
2028	4,381
Next 5 years	19,208
Defined Benefit Plan, Expected Future Benefit Payments Total	41,990
Total	$ 41,990

Debt and Financing Arrangements (Debt Maturities) (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Debt and Financing Arrangements
2024	$ 36,268
2025	105,838
2026	0
2027	0
2028	0
Thereafter	0
Total	$ 142,106

Taxes (Schedule of Gross Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning Balance	$ 18,064	$ 48,963	$ 48,116
Additions based on tax positions related to the current year	3,019	5,446	3,467
Additions for tax positions related to the prior year	731	768	3,931
Increases for tax positions of prior years	1,485
Reductions for tax positions of prior years		(125)	(2,868)
Reductions as a result of lapses in the statute of limitations	(2,732)	(36,988)	(3,683)
Ending Balance	$ 20,567	$ 18,064	$ 48,963

Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Loss Contingencies [Line Items]
Amount accrued	$ 0	$ 2,000
Future commitments	221,200
Surety Bonds Outstanding	552,500
Cash collateral for surety bond	5,600
Reclamation-related obligations	255,740	235,736
Contribution to fund asset retirement obligations	6,273	$ 115,993	$ 20,000
Securitization and Inventory Facilities
Loss Contingencies [Line Items]
Letters of credit outstanding	76,400
Asset retirement obligations
Loss Contingencies [Line Items]
Surety Bonds Outstanding	455,700
Cash collateral for surety bond	600
Reclamation-related obligations	261,800
Contribution to fund asset retirement obligations	$ 142,300

Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Nov. 30, 2020	Nov. 03, 2020
Statutory Accounting Practices
Restricted Cash Current Customer Deposits	$ 1.1	$ 1.1
Mineral rights	215.6	239.4
Deferred finance costs, net	1.0	1.6
Deferred finance costs, current	0.6	0.6
Final contribution to the plan	3.2
Debt instrument, face amount			$ 155.3
Interest rate			5.25%
Convertible Notes
Statutory Accounting Practices
Debt instrument, face amount				$ 155.3
Interest rate				5.25%
Cash on convertible notes	58.4	208.1
Principal amount of convertible notes	$ 13.2	$ 142.1
Paid-in Capital
Statutory Accounting Practices
Cash on convertible notes			$ 39.2
Retained Earnings
Statutory Accounting Practices
Cash on convertible notes			$ 6.7
ASU 2020-06
Statutory Accounting Practices
Diluted earnings per share		$ 65.28
Diluted earnings per share, decrease		$ 1.40
Minimum
Statutory Accounting Practices
Operating lease, remaining lease terms	1 year
Maximum
Statutory Accounting Practices
Operating lease, remaining lease terms	3 years
Exploration and production equipment \| Minimum
Statutory Accounting Practices
Estimated useful life	1 year
Exploration and production equipment \| Maximum
Statutory Accounting Practices
Estimated useful life	16 years
Building and building improvements \| Minimum
Statutory Accounting Practices
Estimated useful life	5 years
Building and building improvements \| Maximum
Statutory Accounting Practices
Estimated useful life	20 years
Mining properties and mineral rights \| Minimum
Statutory Accounting Practices
Operating lease, remaining lease terms	10 years
Mining properties and mineral rights \| Maximum
Statutory Accounting Practices
Operating lease, remaining lease terms	50 years

Accumulated Other Comprehensive Income (Loss) (Tables)

12 Months Ended

Dec. 31, 2023

Accumulated Other Comprehensive Income (Loss).

Schedule of Accumulated Other Comprehensive Income (Loss)


			Pension,
			Postretirement				Accumulated
			and Other Post-				Other
	Derivative		Employment		Available-for-		Comprehensive
	Instruments		Benefits		Sale Securities		Income (loss)

	(In thousands)
January 1, 2022	$	(1,763)	$	16,103	$	(182)	$	14,158
Unrealized gains (losses)		223		61,041		(21)		61,243
Amounts reclassified from accumulated other comprehensive income (loss)		1,540		(3,111)		182		(1,389)
Tax effect		—		(12,548)		(35)		(12,583)
Balances at December 31, 2022	$	—	$	61,485	$	(56)	$	61,429
Unrealized (losses) gains		—		(8,506)		9		(8,497)
Amounts reclassified from accumulated other comprehensive income (loss)		—		(15,858)		30		(15,828)
Tax effect		—		1,662		16		1,678
Balances at December 31, 2023	$	—	$	38,783	$	(1)	$	38,782

Schedule of Comprehensive Income Reclassifications


	December 31,		December 31,		Line Item in the Condensed Consolidated
Details About AOCI Components	2023		2022		Income Statements

Interest rate hedges	$	—	$	(112)	Interest expense
Interest rate hedges (ineffective portion)		—		(1,428)	Net loss resulting from early retirement of debt
		—		—	Provision for income taxes
	$	—	$	(1,540)	Net of tax

Pension, postretirement and other post-employment benefits
Amortization of actuarial gains, net ¹	$	11,208	$	2,193	Non-service related pension and postretirement benefit credits (costs)
Amortization of prior service credits		98		147	Non-service related pension and postretirement benefit credits
Pension Termination/Settlement		4,552		771	Non-service related pension and postretirement benefit credits (costs)
	$	15,858	$	3,111	Total before tax
		(1,662)		(674)	Provision for income taxes
	$	14,196	$	2,437	Net of tax

Available-for-sale securities ²	$	(30)	$	(182)	Interest and investment income
		16		39	Provision for income taxes
	$	(14)	$	(143)	Net of tax

¹ Production-related benefits and workers’ compensation costs are included in costs of sales.

² The gains and losses on sales of available-for-sale-securities are determined on a specific identification basis.

Stock-Based Compensation and Other Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2023

Stock-Based Compensation and Other Incentive Plans

Schedule of Restricted Stock Units Activity


	Time Based Awards			Performance Based Awards
		Weighted			Weighted
		Average			Average
	Restricted	Grant-Date		Restricted	Grant-Date
	Stock Units	Fair Value		Stock Units	Fair Value
(Shares in thousands)
Outstanding at January 1, 2023	359	$	74.14	407	$	74.68
Granted & Reinvested	57		136.55	221		95.83
Forfeited/Canceled	(1)		98.82	(1)		145.11
Vested	(186)		70.56	(324)		48.45
Unvested outstanding at December 31, 2023	229	$	92.41	303	$	117.85