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Document And Entity Information - shares	9 Months Ended
Document And Entity Information - shares	Sep. 30, 2011	Nov. 07, 2011
Document and Entity Information [Abstract]
Entity Registrant Name	ARCH COAL INC
Entity Central Index Key	0001037676
Document Type	10-Q
Document Period End Date	Sep. 30, 2011
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q3
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		211,618,197

Condensed Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Condensed Consolidated Statements Of Income
Revenues	$ 1,198,673	$ 874,705	$ 3,057,139	$ 2,350,874
COSTS, EXPENSES AND OTHER
Cost of sales	952,850	651,853	2,322,124	1,773,464
Depreciation, depletion and amortization	123,026	92,857	301,746	269,135
Amortization of acquired sales contracts, net	(12,186)	10,038	(4,753)	26,005
Selling, general and administrative expenses	33,276	26,999	92,750	89,509
Change in fair value of coal derivatives and coal trading activities, net	8,360	1,832	9,248	12,296
Acquisition and transition costs related to ICG	4,694		53,360
Gain on Knight Hawk transaction				(41,577)
Other operating income, net	(3,613)	(7,221)	(9,019)	(15,004)
Total operating expenses	1,106,407	776,358	2,765,456	2,113,828
Income from operations	92,266	98,347	291,683	237,046
Interest expense, net:
Interest expense	(77,694)	(37,698)	(154,523)	(107,906)
Interest income	840	927	2,341	1,888
Interest expense, net	(76,854)	(36,771)	(152,182)	(106,018)
Other non-operating expense:
Bridge financing costs related to ICG			(49,490)
Net loss resulting from early retirement of debt	(1,708)	(6,776)	(1,958)	(6,776)
Other non-operating expense, Total	(1,708)	(6,776)	(51,448)	(6,776)
Income before income taxes	13,704	54,800	88,053	124,252
Provision for (benefit from) income taxes	(5,583)	7,941	5,103	12,889
Net income	19,287	46,859	82,950	111,363
Less: Net income attributable to noncontrolling interest	(231)	(181)	(822)	(325)
Net income attributable to Arch Coal, Inc.	$ 19,056	$ 46,678	$ 82,128	$ 111,038
EARNINGS PER COMMON SHARE
Basic earnings per common share	$ 0.09	$ 0.29	$ 0.45	$ 0.68
Diluted earnings per common share	$ 0.09	$ 0.29	$ 0.45	$ 0.68
Basic weighted average shares outstanding	211,337	162,391	182,898	162,384
Diluted weighted average shares outstanding	211,974	163,174	183,850	163,128
Dividends declared per common share	$ 0.11	$ 0.1	$ 0.32	$ 0.29

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 158,509	$ 93,593
Restricted cash	21,428
Trade accounts receivable	342,721	208,060
Other receivables	83,579	44,260
Inventories	346,331	235,616
Prepaid royalties	29,163	33,932
Deferred income taxes	15,795
Coal derivative assets	2,595	15,191
Other	107,462	104,262
Total current assets	1,107,583	734,914
Property, plant and equipment, net	7,703,280	3,308,892
Other assets:
Prepaid royalties	96,869	66,525
Goodwill	539,963	114,963
Deferred income taxes	9,217	361,556
Equity investments	224,684	177,451
Other	173,665	116,468
Total other assets	1,044,398	836,963
Total assets	9,855,261	4,880,769
Current liabilities:
Accounts payable	293,446	198,216
Coal derivative liabilities	5,824	4,947
Deferred income taxes		7,775
Accrued expenses and other current liabilities	379,707	245,411
Current maturities of debt and short-term borrowings	47,156	70,997
Total current liabilities	726,133	527,346
Long-term debt	3,841,330	1,538,744
Asset retirement obligations	415,877	334,257
Accrued pension benefits	16,235	49,154
Accrued postretirement benefits other than pension	88,820	37,793
Accrued workers' compensation	64,421	35,290
Deferred income taxes	880,487
Other noncurrent liabilities	277,490	110,234
Total liabilities	6,310,793	2,632,818
Redeemable noncontrolling interest	11,261	10,444
Stockholders' equity:
Common stock, $0.01 par value, authorized 260,000 shares, issued 213,099 shares and 164,117 shares, respectively	2,135	1,645
Paid-in capital	3,012,628	1,734,709
Treasury stock, 1,512 shares at September 30, 2011 and December 31, 2010, at cost	(53,848)	(53,848)
Retained earnings	586,067	561,418
Accumulated other comprehensive loss	(13,775)	(6,417)
Total stockholders' equity	3,533,207	2,237,507
Total liabilities and stockholders' equity	$ 9,855,261	$ 4,880,769

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares shares in Thousands	Sep. 30, 2011	Dec. 31, 2010
Stockholders' equity:
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	260,000	260,000
Additional common stock, shares issued	213,099	164,117
Treasury stock, shares	1,512	1,512

Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
OPERATING ACTIVITIES
Net income	$ 82,950	$ 111,363
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation, depletion and amortization	301,746	269,135
Amortization of acquired sales contracts, net	(4,753)	26,005
Bridge financing costs related to ICG	49,490
Net loss resulting from early retirement of debt	1,958	6,776
Write down of assets acquired from ICG	7,316
Prepaid royalties expensed	26,880	26,190
Employee stock-based compensation expense	9,019	9,640
Amortization relating to financing activities	9,854	6,630
Gain on Knight Hawk transaction		(41,577)
Changes in:
Receivables	(35,874)	(48,718)
Inventories	(23,716)	21,818
Coal derivative assets and liabilities	15,199	14,116
Accounts payable, accrued expenses and other current liabilities	3,742	20,879
Income taxes, net	(21,971)	(1,923)
Deferred income taxes	23,572	(7,561)
Other	25,955	43,907
Cash provided by operating activities	471,367	456,680
INVESTING ACTIVITIES
Acquisition of ICG, net of cash acquired	(2,894,339)
Increase in restricted cash	(5,939)
Capital expenditures	(215,899)	(221,583)
Proceeds from dispositions of property, plant and equipment	25,133	252
Purchases of investments and advances to affiliates	(56,827)	(16,740)
Additions to prepaid royalties	(26,135)	(23,715)
Cash used in investing activities	(3,174,006)	(261,786)
FINANCING ACTIVITIES
Proceeds from the issuance of senior notes	2,000,000	500,000
Proceeds from the issuance of common stock, net	1,267,776
Payments to retire debt	(604,096)	(505,627)
Net increase (decrease) in borrowings under lines of credit and commercial paper program	283,096	(118,337)
Net payments on other debt	(8,792)	(9,794)
Debt financing costs	(114,587)	(12,630)
Dividends paid	(57,470)	(47,121)
Issuance of common stock under incentive plans	1,628	339
Contribution from noncontrolling interest		891
Cash provided by (used in) financing activities	2,767,555	(192,279)
Increase in cash and cash equivalents	64,916	2,615
Cash and cash equivalents, beginning of period	93,593	61,138
Cash and cash equivalents, end of period	$ 158,509	$ 63,753

Basis Of Presentation	9 Months Ended
Basis Of Presentation	Sep. 30, 2011
Basis Of Presentation [Abstract]
Basis of Presentation	1. Basis of Presentation The accompanying unaudited condensed consolidated financial statements include the accounts of Arch Coal, Inc. and its subsidiaries and controlled entities (the "Company"). The Company's primary business is the production of steam and metallurgical coal from surface and underground mines located throughout the United States, for sale to utility, industrial and export markets. On June 15, 2011, the Company acquired International Coal Group, Inc. ("ICG"), as described in Note 3, "Business Combinations". The Company operates 23 mining complexes in West Virginia, Kentucky, Maryland, Virginia, Illinois, Wyoming, Colorado and Utah. All subsidiaries (except as noted below) are wholly-owned. Intercompany transactions and accounts have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial reporting and U.S. Securities and Exchange Commission regulations. In the opinion of management, all adjustments, consisting of normal, recurring accruals considered necessary for a fair presentation, have been included. Results of operations for the three and nine month periods ended September 30, 2011 are not necessarily indicative of results to be expected for the year ending December 31, 2011. These financial statements should be read in conjunction with the audited financial statements and related notes as of and for the year ended December 31, 2010 included in the Company's Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission. The Company owns a 99% membership interest in a joint venture named Arch Western Resources, LLC ("Arch Western") which operates coal mines in Wyoming, Colorado and Utah. The Company also acts as the managing member of Arch Western.

- Definition

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

+ References

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+ Details

Accounting Policies	9 Months Ended
Accounting Policies	Sep. 30, 2011
Accounting Policies [Abstract]
Accounting Policies	2. Accounting Policies There is no new accounting guidance that is expected to have a significant impact on the Company's financial statements.

Business Combination

9 Months Ended

Sep. 30, 2011

Business Combination [Abstract]

Business Combination

3. Business Combination

On June 15, 2011, the Company completed its acquisition of ICG, a leading coal producer, operating 12 mining complexes in Appalachia and one complex in the Illinois Basin. In addition, one mine is currently under development in Appalachia. The Company acquired all of ICG's outstanding shares of common stock for $3.1 billion. To finance the acquisition, the Company received net proceeds of $1.25 billion from the sale of 48.0 million shares of its common stock and issued $2.0 billion in aggregate principal amount of senior unsecured notes. See Note 4, "Equity Offering" and Note 5, "Debt and Financing Arrangements" for further information about these transactions.

The Company has not finalized the determination of the fair values of the assets acquired and liabilities assumed in the acquisition. The following table summarizes the consideration paid for ICG and the estimated amounts of assets acquired and liabilities assumed that were recognized at the acquisition date:


		(In millions)
Consideration paid, net of cash acquired	$	2,894.4
Recognized amounts of net tangible and intangible assets acquired and liabilities assumed:
Restricted cash		15.5
Receivables		114.2
Inventories		87.0
Net property, plant and equipment, including mineral rights		4,510.6
Goodwill		425.0
Other assets		49.2
Accounts payable		(82.6	)
Other accrued expenses and current liabilities		(61.5	)
Debt		(604.8	)
Litigation accrual		(106.0	)
Accrued postretirement benefits		(47.7	)
Asset retirement obligation		(80.4	)
Coal supply agreements, net		(98.8	)
Deferred income taxes, net		(1,189.9	)
Other		(35.4	)
Net tangible and intangible assets acquired	$	2,894.4

During the third quarter of 2011, the following adjustments were made to the purchase price and the provisional fair values:


		(In millions)
Inventories		9.5
Net property, plant and equipment, including mineral rights		(5.8	)
Coal supply agreements, net		(21.2	)
Other		1.5
Purchase price adjustment – cash received	$	(16.0	)

The adjustments to the provisional fair values result from additional information obtained about facts in existence at the acquisition date. Adjustments to provisional fair values are assumed to have been made as of the acquisition date. As a result, cost of sales for the second quarter of 2011 would have been $5.6 million higher than was previously reported. The results in the condensed consolidated statements of income reflect this adjustment as if it had been recorded originally in the second quarter of 2011.

The Company's efforts to value the assets acquired and liabilities assumed are ongoing. Notably, the valuation report that will support the fair value of the fixed assets, coal reserves and goodwill acquired has not yet been completed. The estimated assigned value of goodwill in the table above represents the present value of the estimated synergies from the acquisition. The fair values above could change substantially when the valuation report is received.

Any goodwill related to the acquisition is not expected to be deductible for tax purposes. The allocation of goodwill to reporting units will not be completed until the valuation process is completed.

The revenues and income before income taxes related to the acquired operations that have been included in the consolidated statements of income for the three months ended September 30, 2011 were $295.6 million and $34.9 million, respectively. The revenues and income before income taxes related to the acquired operations that have been included in the consolidated statements of income since the date of acquisition were $343.6 million and $43.6 million, respectively.

The following unaudited pro forma information has been prepared for illustrative purposes and assumes that the business combination occurred on January 1, 2010. The unaudited pro forma results have been prepared based upon ICG's historical results and estimates of the ongoing effects of the transactions that the Company believes are reasonable and supportable. The results are not necessarily reflective of the consolidated results of operations had the acquisition actually occurred on January 1, 2010, nor are they indicative of future operating results.

The unaudited supplemental pro forma financial information of the combined entity follows:


	Three Months Ended September 30				Nine Months Ended September 30
	2011		2010		2011		2010
				(In millions)
Total revenues
As reported	$	1,198.7	$	874.7	$	3,057.1	$	2,350.9
Pro forma	$	1,198.7	$	1,176.9	$	3,596.8	$	3,212.6

Income (loss) before income taxes
As reported	$	13.7	$	54.8	$	88.1	$	124.3
Pro forma	$	22.3	$	47.5	$	72.6	$	(66.9	)

The pro forma income before income taxes includes adjustments to operating costs to reflect the new basis in assets acquired and interest expense to reflect the debt incurred to finance the acquisition. In addition, the following pre-tax costs and expenses reflected in the income before income taxes for the three and nine month periods ended September 30, 2011 reported in the condensed consolidated statement of income are reflected in the pro forma results as of January 1, 2010.


		Three Months Ended		Nine Months Ended
		September 30, 2011		September 30, 2011
		(In thousands)
Costs of completing the acquisition - Arch	$	1,717	$	29,569
Costs of completing the acquisition - ICG		—		23,503
Severance costs		2,977		16,475
Write off of acquired assets		—		7,316
Bridge financing fees		—		49,490
	$	4,694	$	126,353

Severance costs represent both change in control payments to executives and severance for employees terminated after the acquisition. The acquired asset write-off relates to a preparation plant and loadout of an acquired ICG mining operation. The acquired operation has been combined with an existing operation of the Company, and will utilize an existing facility.

Anticipated synergies are not reflected in the pro forma results.

In conjunction with the acquisition, the Company has $21.4 million of restricted cash at September 30, 2011 to provide collateral for ICG letters of credit until they can be eliminated or replaced and to fund change in control payments for executives and the board of directors.

- Definition

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

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+ Details

Equity Offering	9 Months Ended
Equity Offering	Sep. 30, 2011
Equity Offering [Abstract]
Equity Offering	4. Equity Offering On June 8, 2011, the Company sold 48 million shares of its common stock at a public offering price of $27.00 per share. The $1.25 billion in net proceeds from the issuance were used to finance the acquisition of ICG. On July 8, 2011, the Company issued an additional 0.7 million shares of its common stock under the same terms and conditions to cover underwriters' over-allotments for net proceeds of $18.4 million.

- Definition

The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable). Including, but not limited to: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms, and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables, effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
-Number 12
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 4
-Section 08
-Paragraph d

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 1
-Section B
-Paragraph 7, 11A
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 129
-Paragraph 2, 3, 4, 5, 6, 7, 8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Article 4

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30, 31
-Article 5

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section C

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Paragraph 2
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Reference 15: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 17: http://www.xbrl.org/2003/role/presentationRef
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Reference 20: http://www.xbrl.org/2003/role/presentationRef
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Reference 21: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 22: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29-31)
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Reference 23: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187143-122770

+ Details

Debt

9 Months Ended

Sep. 30, 2011

Debt [Abstract]

Debt

5. Debt


		September 30,		December 31,
		2011		2010
		(In thousands)
Commercial paper	$	—	$	56,904
Indebtedness to banks under credit facilities		340,000		—
6.75% senior notes ($450.0 million face value) due July 1, 2013		451,132		451,618
8.75% senior notes ($600.0 million face value) due August 1, 2016		588,496		587,126
7.00% senior notes due June 15, 2019 at par		1,000,000		—
7.25% senior notes due October 1, 2020 at par		500,000		500,000
7.25% senior notes due June 15, 2021 at par		1,000,000		—
Other		8,858		14,093
		3,888,486		1,609,741
Less current maturities of debt and short-term borrowings		47,156		70,997
Long-term debt	$	3,841,330	$	1,538,744

The current maturities of debt include contractual maturities, as well as amounts borrowed that are supported by credit facilities that have a term of less than one year and amounts borrowed under credit facilities with terms longer than one year that the Company does not intend to refinance on a long-term basis, based on cash projections and management's plans.

2019 and 2021 Senior Notes

On June 14, 2011, the Company entered into an indenture in conjunction with the issuance of the 7.00% senior notes due 2019 ("2019 Notes") and the 7.25% senior notes due 2021 ("2021 Notes") as discussed in Note 3, "Business Combinations." Interest is payable on the 2019 Notes and 2021 Notes on June 15 and December 15 of each year, commencing December 15, 2011.

At any time prior to June 15, 2014, the Company may redeem up to 35% of the aggregate principal amount of each of the 2019 Notes and 2021 Notes, plus accrued and unpaid interest, with the net proceeds from certain equity offerings. The Company may redeem the 2019 Notes prior to June 15, 2015 and the 2021 Notes prior to June 15, 2016 at the respective make-whole prices set forth in the indenture. On or after June 15, 2015, the Company may redeem the 2019 Notes for cash at redemption prices, reflected as a percentage of the principal amount, of: 103.5% from June 15, 2015 through June 14, 2016; 101.75% from June 15, 2016 through June 14, 2017; and 100% beginning on June 15, 2017. On or after June 15, 2016, the Company may redeem the 2021 Notes for cash at redemption prices, reflected as a percentage of the principal amount, of: 103.625% from June 15, 2016 through June 14, 2017; 102.417% from June 15, 2017 through June 14, 2018; 101.208% from June 15, 2018 through June 14, 2019 and 100% beginning on June 15, 2019. In each case, accrued and unpaid interest at the redemption date is due upon redemption. Upon a change in control, the Company is required to make a tender offer for both series of notes at a price of 101% of the principal amount.

The 2019 Notes and 2021 Notes are guaranteed by substantially all of the Company's subsidiaries, including the newly acquired subsidiaries of ICG and excluding Arch Western, its subsidiaries and Arch Receivable Company, LLC and the Company's subidiaries outside the U.S. The Company incurred financing fees of $44.2 million related to the issuance of these notes.

The Company and the guarantor subsidiaries entered into a registration rights agreement (the "Registration Rights Agreement") in connection with the issuance and sale of the 2019 Notes and 2021 Notes. Pursuant to the Registration Rights Agreement, the Company and the guarantor subsidiaries agreed to file a registration statement with the Securities and Exchange Commission to register an exchange offer pursuant to which the Company will offer to exchange a like aggregate principal amount of senior notes identical in all material respects to the 2019 Notes and 2021 Notes, except for terms relating to additional interest and transfer restrictions, for any or all of the outstanding 2019 Notes and 2021 Notes. Pursuant to the Registration Rights Agreement, the Company must use commercially reasonable efforts to cause the registration statement to become effective as soon as practicable and to complete the exchange offer no later than June 13, 2012. Should those events not occur within the specified time frame, the applicable interest rates on the 2019 Notes and the 20121 Notes shall be increased by one-quarter of one percent per annum for the first 90 days following the occurrence of such failure. Such interest rate will increase by an additional one-quarter of one percent per annum thereafter at the end of each subsequent 90-day period up to a maximum aggregate increase of one percent per annum. Once any of the required events occur, the interest rates will revert to the rate specified in the indenture governing the 2019 Notes and 2021 Notes.

ICG Debt

Upon the closing of the ICG acquisition, the Company gave a 30-day redemption notice to the Trustee of ICG's 9.125% senior notes and legally discharged its obligation under the 9.125% senior notes by depositing $260.7 million with the Trustee to redeem the debt. On July 14, 2011, all of the outstanding 9.125% senior notes were redeemed at an aggregate price of $251.4 million, including the required make-whole premium, plus accrued interest of $5.2 million, and the remainder of the deposit was returned to the Company.

At the acquisition date, ICG's 4.00% convertible senior notes with a fair value of $298.5 million and 9.00% convertible senior notes with a fair value of $1.7 million ("convertible notes") became convertible into cash, pursuant to the amended indentures governing the convertible notes, at a calculated conversion rate of $2,614.6848 for each $1,000 in principal amount surrendered for conversion for the 4.00% convertible notes and $2,392.73414 for the 9.00% convertible notes for conversions occurring prior to August 17, 2011.

Other ICG debt, with a fair value of approximately $54.0 million at the acquisition date, consisted mainly of equipment notes and insurance notes payable.

The Company recognized net losses of $1.7 million and $2.0 million during the three and nine months ended September 30, 2011, respectively on the early extinguishment of ICG's debt, including the conversions of the 4.00% and 9.00% convertible notes described above. The remaining amounts outstanding under the convertible notes and other ICG debt is included in "other" in the debt table above.

Credit Facilities and Commercial Paper

On June 14, 2011, the Company amended and restated its secured credit facility to allow for up to $2.0 billion in borrowings. Borrowings under this credit facility bear interest at a floating rate based on LIBOR determined by reference to the Company's leverage ratio, as calculated in accordance with the credit agreement. The credit facility has a five-year term that expires on June 14, 2016 and is secured by substantially all of the Company's assets as well as its ownership interests in substantially all of its subsidiaries, excluding its ownership interests in Arch Western and its subsidiaries. Commitment fees of 0.50% per annum are payable on the average unused daily balance of the revolving credit facility. The Company paid and deferred $20.7 million in financing fees related to the amendment of this agreement. Financial covenant requirements may restrict the amount of unused capacity available to the Company for borrowings and letters of credit.

On June 14, 2011, the Company terminated its commercial paper placement program and the supporting credit facility.

Availability

As of September 30, 2011 the Company had $300.0 million of borrowings outstanding under the amended and restated secured credit facility and $40.0 million of borrowings outstanding under its accounts receivable securitization program. As of September 30, 2011, the Company had availability of approximately $1.0 billion under all lines of credit, as limited by customary financial covenants that may limit the Company's total debt based on defined earnings measurements. The Company also had outstanding letters of credit of $141.0 million as of September 30, 2011.

- 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 + Details

Acquired Sales Contracts

9 Months Ended

Sep. 30, 2011

Acquired Sales Contracts [Abstract]

Acquired Sales Contracts

6. Acquired Sales Contracts

Coal supply agreements (sales contracts) acquired in a business combination are capitalized at their fair value and amortized over the tons of coal shipped during the term of the contract. The fair value of a sales contract is determined by discounting the cash flows attributable to the difference between the contract price and the prevailing forward prices for the tons under contract at the date of acquisition. Below are the acquired sales contracts reflected in the condensed consolidated balance sheets:


		September 30, 2011						December 31, 2010
		Assets		Liabilities				Assets			Liabilities
		(In thousands)						(In thousands)
Acquired fair value	$	145,213		$	170,341		$	114,453		$	40,654
Accumulated amortization		(105,845	)		(42,877	)		(82,376	)		(14,613	)
Total	$	39,368		$	127,464		$	32,077		$	26,041
Net total				$	88,096		$	6,036

Balance Sheet classification:
Other current	$	23,474		$	58,049		$	25,063		$	5,615
Other noncurrent	$	15,894		$	69,415		$	7,014		$	20,426

Above-market contracts with a fair value of $30.8 million and below-market contracts with a fair value of $129.7 million were acquired from ICG. Of these amounts, $13.7 million and $52.3 million were classified as current assets and current liabilities, respectively, at September 30, 2011. See Note 3, "Business Combinations" for discussion of purchase price adjustments.

The Company anticipates amortization income of all acquired sales contracts, based upon the fair value assigned to acquired ICG sales contracts and expected shipments in the next five years, to be approximately $29 million for the remainder of 2011, $20 million in 2012, $7 million in 2013, $8 million in 2014, $13 million in 2015 and $8 million in 2016.

Investments

9 Months Ended

Sep. 30, 2011

Investments [Abstract]

Investments

7. Equity 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. Below are the equity method investments reflected in the condensed consolidated balance sheets:


		Knight Hawk			DKRW			DTA			Tenaska			Millennium			Tongue River		Total
											(In thousands)
Balance at December 31, 2010	$	131,250		$	21,961		$	14,472		$	9,768		$	—		$	—	$	177,451
Investments in affiliates		—			—			—			5,500			25,000			12,989		43,489
Advances to (distributions from) affiliates, net		(11,450	)		—			4,394			—			1,900			—		(5,156	)
Equity in comprehensive income (loss)		15,807			(1,631	)		(3,713	)		(2	)		(1,561	)		—		8,900
Balance at September 30, 2011	$	135,607		$	20,330		$	15,153		$	15,266		$	25,339		$	12,989	$	224,684

Notes receivable from investees:
Balance at December 31, 2010	$	1,700		$	18,100		$	—		$	4,100		$	—		$	—	$	23,900
Balance at September 30, 2011		—			28,417			—			4,777			—			—		33,194

In July 2011, the Company purchased a 33% membership interest in the Tongue River Holding Company, LLC ("Tongue River") joint venture. Tongue River will construct and develop a railway line near Miles City, Montana and the Company's Otter Creek reserves. The Company has the right, upon completion of the railway line or under other prescribed circumstances, to require the other investors to purchase all of the Company's units in the venture at an amount equal to the capital contributions made by the Company at that time, less any distributions received.

In January 2011, the Company purchased a 38% ownership interest in Millennium Bulk Terminals-Longview, LLC ("Millennium"), the owner of a brownfield bulk commodity terminal on the Columbia River near Longview, Washington, for $25.0 million, plus additional future consideration upon the completion of certain project milestones. Millennium continues to work on obtaining the required approvals and necessary permits to complete dredging and other upgrades to enable coal, alumina and cementitious material shipments through the terminal. The Company will control 38% of the terminal's throughput and storage capacity, in order to facilitate export shipments of coal off the west coast of the United States.

The Company may be required to make future contingent payments of up to $70.9 million related to development financing for certain of its equity investees. The Company's obligation to make these payments, as well as the timing of any payments required, is contingent upon a number of factors, including project development progress, receipt of permits and construction financing.

- Definition

The entire disclosure for equity investment, or group of investments, for which combined disclosure is appropriate, including: (a) the name of each investee and percentage of ownership of common stock, (b) accounting policies for investments in common stock, (c) difference between the amount at which the investment is carried and the amount of underlying equity in net assets and the accounting treatment of the difference, (d) the total fair value of each identified investment for which a market value is available, (e) summarized information as to assets, liabilities, and results of operations of the investees (for investments in unconsolidated subsidiaries, common stock of joint ventures, or other investments using the equity method), and (f) material effects of possible conversions, exercises, or contingent issuances of the investee. Other disclosures include (a) the names of any investee in which the investor owns 20 percent or more of the voting stock and investment is not accounted for using the equity method, and the reasons why not, and (b) the names of any investee in which the investor owns less than 20 percent of the voting stock and the investment is accounted for using the equity method, and the reasons why it is.

+ References + Details

Derivatives

9 Months Ended

Sep. 30, 2011

Derivatives [Abstract]

Derivatives

8. Derivatives

The Company generally utilizes derivative financial instruments to manage exposures to commodity prices. Additionally, the Company may hold certain coal derivative financial instruments for trading purposes.

All derivative financial instruments are recognized in the balance sheet at fair value. In a fair value hedge, the Company hedges the risk of changes in the fair value of a firm commitment, typically a fixed-price coal sales contract. Changes in both the hedged firm commitment and the fair value of a derivative used as a hedge instrument in a fair value hedge are recorded in earnings. In a cash flow hedge, the Company hedges the risk of changes in future cash flows related to a forecasted purchase or sale. Changes in the fair value of the derivative instrument used as a hedge instrument in a cash flow hedge are recorded in other comprehensive income. Amounts in other comprehensive income are reclassified to earnings when the hedged transaction affects earnings and are classified in a manner consistent with the transaction being hedged. The Company formally documents the relationships between hedging instruments and the respective hedged items, as well as its risk management objectives for hedge transactions.

The Company evaluates the effectiveness of its hedging relationships both at the hedge's inception and on an ongoing basis. Any ineffective portion of the change in fair value of a derivative instrument used as a hedge instrument in a fair value or cash flow hedge is recognized immediately in earnings. The ineffective portion is based on the extent to which exact offset is not achieved between the change in fair value of the hedge instrument and the cumulative change in expected future cash flows on the hedged transaction from inception of the hedge in a cash flow hedge or the change in the fair value of the firm commitment in a fair value hedge.

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 90 to100 million gallons of diesel fuel for use in its operations during 2012. To reduce the volatility in the price of diesel fuel for its operations, the Company uses forward physical diesel purchase contracts, as well as heating oil swaps and purchased call options. At September 30, 2011, the Company had protected the price of approximately 70% of its expected purchases for the remainder of fiscal year 2011 and 55% for fiscal year 2012.

At September 30, 2011, the Company held heating oil swaps and purchased call options for approximately 68 million gallons for the purpose of managing the price risk associated with future diesel purchases. Since the changes in the price of heating oil highly correlate to changes in the price of the hedged diesel fuel purchases, the heating oil swaps and purchased call options qualify for cash flow hedge accounting.

The Company also purchased call options to hedge the fuel surcharges on its barge and rail shipments that cover increases in diesel fuel prices. These positions reduce the Company's risk of cash flow fluctuations related to these surcharges but the positions are not accounted for as hedges. At September 30, 2011, Company held purchased call options for approximately 19.1 million gallons for the purpose of managing the fluctuations in cash flows associated with fuel surcharges on future shipments.

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 September 30, 2011, the Company held derivatives for risk management purposes totaling 0.5 million tons of coal sales and 0.5 million tons of coal purchases that are expected to settle during the remainder of 2011, 1.7 million tons of coal sales and 0.2 million tons of coal purchases that are expected to settle in 2012, 0.7 million tons of coal sales that are expected to settle in 2013, 1.4 million tons of coal sales that are expected to settle in 2014 and 0.7 million tons of coal sales that are expected to settle in 2015.

Coal trading positions

The Company may sell or purchase forward contracts, swaps and options in the over-the-counter coal market for trading purposes. The Company is exposed to the risk of changes in coal prices on the value of its coal trading portfolio. The estimated future realization of the value of the trading portfolio is $2.4 million of gains for the remainder of 2011, $0.9 million of losses in 2012 and $1.0 million of losses in 2013.

Tabular derivatives disclosures

The Company's contracts with certain of its counterparties to 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 condensed consolidated balance sheets. The amounts shown in the table below represent the fair value position of individual contracts, regardless of the net position presented in the accompanying condensed consolidated balance sheets. The fair value and location of derivatives reflected in the accompanying condensed consolidated balance sheets are as follows:

Fair Value of Derivatives (in thousands)


		September 30, 2011								December 31, 2010
		Asset			Liability					Asset			Liability
		Derivative			Derivative					Derivative			Derivative
Derivatives Designated as Hedging
Instruments
Heating oil – diesel purchases	$	9,352		$	—				$	13,475		$	—
Coal		2,708			(1,270	)				2,009			(2,350	)
Total		12,060			(1,270	)				15,484			(2,350	)
Derivatives Not Designated as Hedging
Instruments
Heating oil – fuel surcharges		2,202			—					—			—
Coal — held for trading purposes		10,862			(10,365	)				34,445			(24,087	)
Coal		1,812			(6,976	)				1,139			(912	)
Total		14,876			(17,341	)				35,584			(24,999	)
Total derivatives		26,936			(18,611	)				51,068			(27,349	)
Effect of counterparty netting		(12,787	)		12,787					(22,402	)		22,402
Net derivatives as classified in the
balance sheets	$	14,149		$	(5,824	)	$	8,325	$	28,666		$	(4,947	)	$	23,719

Net derivatives as reflected on the balance sheets


			September 30,			December 31,
			2011			2010
Heating oil	Other current assets	$	11,554		$	13,475
Coal	Coal derivative assets		2,595			15,191
	Coal derivative liabilities		(5,824	)		(4,947	)
		$	8,325		$	23,719

The Company had a current asset for the right to reclaim cash collateral of $10.7 million and $10.3 million at September 30, 2011 and December 31, 2010, respectively. These amounts are not included with the derivatives presented in the table above and are included in "other current assets" in the accompanying condensed consolidated balance sheets.

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

Three Months Ended September 30 (in thousands)


	Gain (Loss) Recognized in OCI (Effective Portion)						Gains (Losses) Reclassified from OCI into Income (Effective Portion)							Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)



Derivatives used in
Cash Flow Hedging
Relationships	2011			2010			2011			2010				2011		2010
Heating oil – diesel purchases	$	(6,386	)	$	3,052		$	5,122	(2)	$	93		(2)	$	—	$	—
Coal sales		1,820			1,500			466	(1)		(226	)	(1)		—		—
Coal purchases		(1,274	)		(2,535	)		—	(2)		(866	)	(2)		—		—
Totals	$	(5,840	)	$	2,017		$	5,588		$	(999	)		$	—	$	—


Derivatives Not Designated as	Gain (Loss)
Hedging Instruments	2011				2010
Coal — unrealized	$	(6,131	)	(3)	$	(993	)	(3)
Coal — realized	$	166		(4)	$	1,079		(4)
Heating oil — fuel surcharges — unrealized	$	(2,501	)	(4)	$	—		(4)

Location in Statement of Income:

(1) Revenues

(2) Cost of sales

(3) Change in fair value of coal derivatives and coal trading activities, net

(4) Other operating income, net

During the three months ended September 30, 2011 and 2010, the Company recognized net unrealized and realized losses of $2.2 million and $0.8 million, respectively, related to its trading portfolio (including derivative and non-derivative contracts). These balances are included in the caption "Change in fair value of coal derivatives and coal trading activities, net" in the accompanying condensed consolidated statements of income and are not included in the previous table.

Nine Months Ended September 30 (in thousands)


		Gain (Loss) Recognized in OCI (Effective Portion)						Gains (Losses) Reclassified from OCI into Income (Effective Portion)							Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)



Derivatives used in
Cash Flow Hedging
Relationships		2011			2010			2011			2010				2011				2010
Heating oil – diesel purchases	$	1,535		$	(5,508	)	$	14,946	(2)	$	(211	)	(2)	$	—			$	—
Coal sales		4,570			(6,138	)		790	(1)		(1,556	)	(1)		—				—
Coal purchases		(2,053	)		5,534			—	(2)		(1,202	)	(2)		—				—
Totals	$	4,052		$	(6,112	)	$	15,736		$	(2,969	)		$	—			$	—

Derivatives Not Designated as														Gain (Loss)
Hedging Instruments														2011				2010
Coal — unrealized														$	(7,550	)	(3)	$	(9,381	)	(3)
Coal — realized														$	313		(4)	$	3,931		(4)
Heating oil — fuel surcharges — unrealized														$	(2,501	)	(4)	$	—		(4)

Location in Statement of Income:

(1) Revenues

(2) Cost of sales

(3) Change in fair value of coal derivatives and coal trading activities, net

(4) Other operating income, net

During the nine months ended September 30, 2011 and 2010, the Company recognized net unrealized and realized losses of $1.7 million and $2.9 million, respectively, related to its trading portfolio (including derivative and non-derivative contracts). These balances are included in the caption "Change in fair value of coal derivatives and coal trading activities, net" in the accompanying condensed consolidated statements of income and are not included in the previous table.

During the next twelve months, based on fair values at September 30, 2011, gains on derivative contracts designated as hedge instruments in cash flow hedges of approximately $9.3 million are expected to be reclassified from other comprehensive income into earnings.

- Definition

The entire disclosure for the entity's entire derivative instruments and hedging activities. Describes an entity's risk management strategies, derivatives in hedging activities and non-hedging derivative instruments, the assets, obligations, liabilities, revenues and expenses arising therefrom, and the amounts of and methodologies and assumptions used in determining the amounts of such items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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+ Details

Inventories

9 Months Ended

Sep. 30, 2011

Inventories [Abstract]

Inventories

9. Inventories


Inventories consist of the following:
		September 30,		December 31,
		2011		2010
		(In thousands)
Coal	$	180,988	$	115,647
Repair parts and supplies, net of allowance		165,343		119,969
	$	346,331	$	235,616

The repair parts and supplies are stated net of an allowance for slow-moving and obsolete inventories of $13.4 million at September 30, 2011, and $12.7 million at December 31, 2010.

Fair Value Measurements

9 Months Ended

Sep. 30, 2011

Fair Value Measurements [Abstract]

Fair Value Measurements

10. Fair Value Measurements

The hierarchy of fair value measurements prioritizes the inputs to valuation techniques used to measure fair value. 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 available-for-sale equity securities and coal 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 commodity contracts (coal and heating oil) 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 (primarily coal and heating oil) valued using modeling techniques, such as Black-Scholes, that require the use of inputs, particularly volatility, that are rarely observable.

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


	Fair Value at September 30, 2011
	Total		Level 1		Level 2			Level 3
				(In thousands)
Assets:
Investments in equity securities	$	5,351	$	5,351	$	—		$	—
Derivatives		14,149		1,018		2,695			10,436
Total assets	$	19,500	$	6,369	$	2,695		$	10,436
Liabilities:
Derivatives	$	5,824	$	—	$	(415	)	$	6,239

The Company's contracts with certain of 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 condensed 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.


	Three Months Ended September 30, 2011			Nine Months Ended September 30, 2011
	Three Months Ended September 30, 2011			Nine Months Ended September 30, 2011
	(In thousands)
Balance, beginning of period	$	10,474		$	9,183
Realized and unrealized losses recognized in earnings, net		(8,016	)		(15,140	)
Realized and unrealized losses recognized in other comprehensive income, net		(6,702	)		(3,227	)
Purchases		9,935			20,407
Issuances		—			(2,160	)
Settlements		(1,494	)		(4,866	)
Balance, end of period	$	4,197		$	4,197

Net unrealized losses during the three and nine month periods ended September 30, 2011 related to level 3 financial instruments held on September 30, 2011 were $11.7 million and $14.7 million, respectively.

Fair Value of Long-Term Debt

At September 30, 2011 and December 31, 2010, the fair value of the Company's senior notes and other long-term debt, including amounts classified as current, was $3.9 billion and $1.7 billion, respectively. Fair values are based upon observed prices in an active market when available or from valuation models using market information.

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44A, 44B
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15C, 15D
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15A
-Subparagraph a-d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15B
-Subparagraph a, b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 3, 10, 14, 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32, 33, 34
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 17-22, 27, 28
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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+ Details

Stock-Based Compensation And Other Incentive Plans	9 Months Ended
Stock-Based Compensation And Other Incentive Plans	Sep. 30, 2011
Stock-Based Compensation and Other Incentive Plans [Abstract]
Stock-Based Compensation And Other Incentive Plans	11. Stock-Based Compensation and Other Incentive Plans During the nine months ended September 30, 2011, the Company granted options to purchase approximately 0.7 million shares of common stock with a weighted average exercise price of $32.18 per share and a weighted average grant-date fair value of $14.18 per share. The options' fair value was determined using the Black-Scholes option pricing model, using a weighted average risk-free rate of 1.92%, a weighted average dividend yield of 1.25% and a weighted average volatility of 57.43%. The options' expected life is 4.5 years and the options vest ratably over three years. The options provide for the continuation of vesting after retirement for recipients that meet certain criteria. The expense for these options will be recognized through the date that the employee first becomes eligible to retire and is no longer required to provide service to earn all or part of the award. The Company also granted 130,950 shares of restricted stock during the nine months ended September 30, 2011 at a weighted average grant-date fair value of $31.30 per share. The restricted stock vests after three years. The Company has a long-term incentive program ("LTI plan") that allows for the award of performance units. The total number of units earned by a participant is based on financial and operational performance measures, and may be paid out in cash or in shares of the Company's common stock. The Company recognizes compensation expense over the three-year term of the grant. Amounts unpaid for all grants under the LTI plan totaled $10.0 million and $6.4 million as of September 30, 2011 and December 31, 2010, respectively. The Company recognized compensation expense from all stock-based and LTI plans of $3.4 million for the three months ended September 30, 2011 and 2010, respectively. The Company recognized compensation expense from all stock-based and LTI plans of $12.6 million and $12.3 million for the nine months ended September 30, 2011 and 2010, respectively. These expenses are primarily included in selling, general and administrative expenses in the accompanying condensed consolidated statements of income.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64, 65, A240
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 93-6
-Paragraph 53
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14

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+ Details

Workers' Compensation Expense

9 Months Ended

Sep. 30, 2011

Workers' Compensation Expense [Abstract]

Workers' Compensation Expense

12. Workers' Compensation Expense

The following table details the components of workers' compensation expense:


	Three Months Ended September 30						Nine Months Ended September 30
	2011			2010			2011			2010
	(In thousands)						(In thousands)
Self-insured occupational disease benefits:
Service cost	$	807		$	182		$	1,246		$	545
Interest cost		619			169			1,177			507
Net amortization		(109	)		(465	)		(370	)		(1,395	)
Total occupational disease		1,317			(114	)		2,053			(343	)
Traumatic injury claims and assessments		5,207			2,642			10,856			6,562
Total workers' compensation expense	$	6,524		$	2,528		$	12,909		$	6,219

Employee Benefit Plans

9 Months Ended

Sep. 30, 2011

Employee Benefit Plans [Abstract]

Employee Benefit Plans

13. Employee Benefit Plans

The following table details the components of pension benefit costs:


	Three Months Ended September 30						Nine Months Ended September 30
	2011			2010			2011			2010
	(In thousands)						(In thousands)
Service cost	$	4,122		$	3,967		$	12,367		$	11,902
Interest cost		4,063			3,955			12,190			11,866
Expected return on plan assets		(5,453	)		(4,848	)		(16,359	)		(14,544	)
Amortization of prior service cost (credit)		(47	)		44			(142	)		130
Amortization of other actuarial losses		2,187			1,782			6,561			5,348
Net benefit cost	$	4,872		$	4,900		$	14,617		$	14,702

The following table details the components of other postretirement benefit costs (credits):


	Three Months Ended September 30						Nine Months Ended September 30
	2011			2010			2011			2010
	(In thousands)						(In thousands)
Service cost	$	1,493		$	378		$	2,416		$	1,132
Interest cost		1,125			520			2,152			1,562
Amortization of prior service credits		(636	)		(591	)		(1,773	)		(1,773	)
Amortization of other actuarial gains		(775	)		(729	)		(2,325	)		(2,188	)
Net benefit cost (credit)	$	1,207		$	(422	)	$	470		$	(1,267	)

- Definition

The entire disclosure for pension and other postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph a
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 106
-Paragraph 518
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 03-2
-Paragraph 8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Principles Board Opinion (APB)
-Number 30
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 10: http://www.xbrl.org/2003/role/presentationRef
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5, 6, 7, 8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Implementation Guide (Q and A)
-Number FAS88
-Paragraph 63
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/topic&trid=2235017

+ Details

Comprehensive Income

9 Months Ended

Sep. 30, 2011

Comprehensive Income [Abstract]

Comprehensive Income

14. Comprehensive Income

Comprehensive income consists of net income and other comprehensive income. Other comprehensive income items are transactions recorded in stockholders' equity during the year, excluding net income and transactions with stockholders.

The following table presents the components of comprehensive income:


		Three Months Ended September 30					Nine Months Ended September 30
	2011			2010		2011			2010
	(In thousands)					(In thousands)
Net income attributable to Arch Coal, Inc.	$	19,056		$	46,678	$	82,128		$	111,038
Other comprehensive income, net of income taxes:
Pension, postretirement and other post-employment benefits,
reclassifications into net income		388			28		1,254			84
Unrealized gains (losses) on available-for-sale securities		(569	)		738		(1,256	)		(178	)
Unrealized gains and losses on derivatives, net of
reclassifications into net income:
Unrealized gains (losses) on derivatives		(3,671	)		1,200		2,703			(3,889	)
Reclassifications of (gains) losses into net income		(3,575	)		639		(10,059	)		1,856
Total comprehensive income	$	11,629		$	49,283	$	74,770		$	108,911

- Definition

The entire disclosure for comprehensive income. Includes, but is not limited to, the following: 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income. Components of comprehensive income include: (1) foreign currency translation adjustments; (2) gains (losses) on foreign currency transactions that are designated as, and are effective as, economic hedges of a net investment in a foreign entity; (3) gains (losses) on intercompany foreign currency transactions that are of a long-term-investment nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements; (4) change in the market value of a futures contract that qualifies as a hedge of an asset reported at fair value; (5) unrealized holding gains (losses) on available-for-sale securities and that resulting from transfers of debt securities from the held-to-maturity category to the available-for-sale category; (6) a net loss recognized as an additional pension liability not yet recognized as net periodic pension cost; and (7) the net gain (loss) and net prior service cost or credit for pension plans and other postretirement benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 14-26
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Publisher FASB
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+ Details

Earnings Per Common Share

9 Months Ended

Sep. 30, 2011

Earnings Per Common Share

Earnings Per Common Share

15. Earnings per Common Share

The following table provides the basis for earnings per share calculations by reconciling basic and diluted weighted average shares outstanding:


	Three Months Ended September 30		Nine Months Ended September 30
	2011	2010	2011	2010
	(In thousands)		(In thousands)
Weighted average shares outstanding:
Basic weighted average shares outstanding	211,337	162,391	182,898	162,384
Effect of common stock equivalents under incentive plans	637	783	952	744
Diluted weighted average shares outstanding	211,974	163,174	183,850	163,128

The effect of options to purchase 3.0 million and 3.4 million shares of common stock were excluded from the calculation of diluted weighted average shares outstanding for the three month periods ended September 30, 2011 and 2010, respectively, because the exercise price of these options exceeded the average market price of the Company's common stock for these periods. The effect of options to purchase 2.1 million and 2.7 million shares of common stock were excluded from the calculation of diluted weighted average shares outstanding for the nine month periods ended September 30, 2011 and 2010, respectively, because the exercise price of these options exceeded the average market price of the Company's common stock for these periods.

Guarantees	9 Months Ended
Guarantees	Sep. 30, 2011
Guarantees
Guarantees	16. Guarantees The Company has agreed to continue to provide surety bonds and letters of credit for the reclamation and retiree healthcare obligations of Magnum Coal Company ("Magnum") related to the properties the Company sold to Magnum on December 31, 2005. Patriot Coal Corporation ("Patriot") acquired Magnum in July 2008. The purchase agreement requires Magnum to reimburse the Company for costs related to the surety bonds and letters of credit and to use commercially reasonable efforts to replace the obligations. If the surety bonds and letters of credit related to the reclamation obligations are not replaced by Magnum within a specified period of time, Magnum must post a letter of credit in favor of the Company in the amounts of the reclamation obligations. As of September 30, 2011, Patriot has replaced $48.9 million of the surety bonds and has posted letters of credit of $32.7 million in the Company's favor. At September 30, 2011, the Company had $38.5 million of surety bonds remaining related to properties sold to Magnum. The surety bonding amounts are mandated by the state and are not directly related to the estimated cost to reclaim the properties. Magnum also acquired certain coal supply contracts with customers who have not consented to the contracts' assignment from the Company to Magnum. The Company has committed to purchase coal from Magnum to sell to those customers at the same price it is charging the customers for the sale. In addition, certain contracts were assigned to Magnum, but the Company has guaranteed Magnum's performance under the contracts. The longest of the coal supply contracts extends to the year 2017. If Magnum is unable to supply the coal for these coal sales contracts then the Company would be required to purchase coal on the open market or supply contracts from its existing operations. At market prices effective at September 30, 2011, the cost of purchasing 10.3 million tons of coal to supply the contracts that have not been assigned over their duration would exceed the sales price under the contracts by approximately $264.3 million, and the cost of purchasing 0.9 million tons of coal to supply the assigned and guaranteed contracts over their duration would exceed the sales price under the contracts by approximately $19.5 million. As the Company does not believe that it is probable that it would have to purchase replacement coal, no losses have been recorded in the consolidated financial statements as of September 30, 2011. However, if the Company would have to perform under these guarantees, it could potentially have a material adverse effect on the business, results of operations and financial condition of the Company. In connection with the Company's acquisition of the coal operations of Atlantic Richfield Company (ARCO) and the simultaneous combination of the acquired ARCO operations and the Company's Wyoming operations into the Arch Western joint venture, the Company agreed to indemnify the other member of Arch Western against certain tax liabilities in the event that such liabilities arise prior to June 1, 2013 as a result of certain actions taken, including the sale or other disposition of certain properties of Arch Western, the repurchase of certain equity interests in Arch Western by Arch Western or the reduction under certain circumstances of indebtedness incurred by Arch Western in connection with the acquisition. If the Company were to become liable, the maximum amount of potential future tax payments is $22.3 million at September 30, 2011, which is not recorded as a liability in the Company's condensed consolidated financial statements. Since the indemnification is dependent upon the initiation of activities within the Company's control and the Company does not intend to initiate such activities, it is remote that the Company will become liable for any obligation related to this indemnification. However, if such indemnification obligation were to arise, it could potentially have a material adverse effect on the business, results of operations and financial condition of the Company.

Contingencies	9 Months Ended
Contingencies	Sep. 30, 2011
Contingencies
Contingencies	17. Contingencies On June 15, 2011, the Company acquired ICG and its subsidiaries. The following matters relate to certain claims and legal actions involving ICG and/or its subsidiaries. Allegheny Energy Supply ("Allegheny"), the sole customer of coal produced at the Company's subsidiary Wolf Run Mining Company's ("Wolf Run") Sycamore No. 2 mine, filed a lawsuit against Wolf Run, Hunter Ridge Holdings, Inc. ("Hunter Ridge"), and ICG in state court in Allegheny County, Pennsylvania on December 28, 2006, and amended its complaint on April 23, 2007. Allegheny claimed that Wolf Run breached a coal supply contract when it declared force majeure under the contract upon idling the Sycamore No. 2 mine in the third quarter of 2006, and that Wolf Run continued to breach the contract by failing to ship in volumes referenced in the contract. The Sycamore No. 2 mine was idled after encountering adverse geologic conditions and abandoned gas wells that were previously unidentified and unmapped. After extensive searching for gas wells and rehabilitation of the mine, it was re-opened in 2007, but with notice to Allegheny that it would necessarily operate at reduced volumes in order to safely and effectively avoid the many gas wells within the reserve. The amended complaint also alleged that the production stoppages constitute a breach of the guarantee agreement by Hunter Ridge and breach of certain representations made upon entering into the contract in early 2005. Allegheny voluntarily dropped the breach of representation claims later. Allegheny claimed that it would incur costs in excess of $100 million to purchase replacement coal over the life of the contract. ICG, Wolf Run and Hunter Ridge answered the amended complaint on August 13, 2007, disputing all of the remaining claims. On November 3, 2008, ICG, Wolf Run and Hunter Ridge filed an amended answer and counterclaim against the plaintiffs seeking to void the coal supply agreement due to, among other things, fraudulent inducement and conspiracy. On September 23, 2009, Allegheny filed a second amended complaint alleging several alternative theories of liability in its effort to extend contractual liability to ICG, which was not a party to the original contract and did not exist at the time Wolf Run and Allegheny entered into the contract. No new substantive claims were asserted. ICG answered the second amended complaint on October 13, 2009, denying all of the new claims. ICG's counterclaim was dismissed on motion for summary judgment entered on May 11, 2010. Allegheny's claims against ICG were also dismissed by summary judgment, but the claims against Wolf Run and Hunter Ridge were not. The court conducted a non-jury trial of this matter beginning on January 10, 2011 and concluding on February 1, 2011. At the trial, Allegheny presented its evidence for breach of contract and claimed that it is entitled to past and future damages in the aggregate of between $228.0 million and $377.0 million. Wolf Run and Hunter Ridge presented their defense of the claims, including evidence with respect to the existence of force majeure conditions and excuse under the contract and applicable law. Wolf Run and Hunter Ridge presented evidence that Allegheny's damages calculations were significantly inflated because it did not seek to determine damages as of the time of the breach and in some instances artificially assumed future non-delivery or did not take into account the apparent requirement to supply coal in the future. On May 2, 2011, the trial court entered a Memorandum and Verdict determining that Wolf Run had breached the coal supply contract and that the performance shortfall was not excused by force majeure. ICG and Allegheny filed post-verdict motions in the trial court and on August 23, 2011, the court denied the parties' motions. The court entered a final judgment on August 25, 2011, in the amount of $104.1 million, which included pre-judgment interest. The parties appealed the lower court's decision to the Superior Court of Pennsylvania. Wolf Run and Hunter Ridge have filed an appeal bond in the amount of $124.9 million. Briefing is scheduled to begin on October 24, 2011, to be completed in early 2012. As of September 30, 2011, the Company has accrued $106.7 million for this lawsuit, including $1.8 million of interest recognized post-acquisition. The ultimate resolution of this matter could result in an outcome which may be materially different than what the Company has accrued. In addition, the Company is a party to numerous claims and lawsuits with respect to various matters. The Company provides for costs related to contingencies when a loss is probable and the amount is reasonably determinable. After conferring with counsel, it is the opinion of management that the ultimate resolution of pending claims, other than as noted above, will not have a material adverse effect on the consolidated financial condition, results of operations or liquidity of the Company.

- Definition

The entire disclosure for commitments and contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 14
-Paragraph 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
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-URI http://asc.fasb.org/extlink&oid=6449706&loc=d3e16207-108621

+ Details

Segment Information

9 Months Ended

Sep. 30, 2011

Segment Information [Abstract]

Segment Information

18. Segment Information

The Company has three reportable business segments, which are based on the major coal producing basins in which the Company operates. Each of these reportable business segments includes a number of mine complexes. The Company manages its coal sales by coal basin, not by individual mine complex. Geology, coal transportation routes to customers, regulatory environments and coal quality are characteristic to a basin. Accordingly, market and contract pricing have developed by coal basin. Mine operations are evaluated based on their per-ton operating costs (defined as including all mining costs but excluding pass-through transportation expenses), as well as on other non-financial measures, such as safety and environmental performance. The Company's reportable segments are the Powder River Basin (PRB) segment, with operations in Wyoming; the Western Bituminous (WBIT) segment, with operations in Utah, Colorado and southern Wyoming; the Appalachia (APP) segment, with operations in West Virginia, Kentucky, Maryland and Virginia. The Appalachia segment includes the acquired ICG operations in Appalachia, as well as the Company's previous Central Appalachia segment. The "Other" operating segment represents primarily the Company's Illinois operations and ADDCAR subsidiary, which manufactures and sells its patented highwall mining system.

Operating segment results for the three and nine months ended September 30, 2011 and 2010 are presented below. Results for the reportable segments include all direct costs of mining, including all depreciation, depletion and amortization related to the mining operations, even if the assets are not recorded at the operating segment level. See discussion of segment assets below. Corporate, Other and Eliminations includes the change in fair value of coal derivatives and coal trading activities, net; corporate overhead; land management; other support functions; and the elimination of intercompany transactions.

The asset amounts below represent an allocation of assets used in the segments' cash-generating activities. The amounts in Corporate, Other and Eliminations represent primarily corporate assets (cash, receivables, investments, plant, property and equipment) as well as unassigned coal reserves, above-market acquired sales contracts and other unassigned assets.


									Other			Corporate,
									Operating			Other and
		PRB		APP			WBIT		Segments			Eliminations			Consolidated
	(In thousands)
Three months ended September 30, 2011
Revenues	$	394,012	$	611,403		$	168,795	$	24,463		$	—		$	1,198,673
Income (loss) from operations		38,630		77,511			24,653		(1,713	)		(46,815	)		92,266
Depreciation, depletion and amortization		42,676		59,576			19,125		3,781			(2,132	)		123,026
Amortization of acquired sales contracts, net		3,802		(16,022	)		—		34			—			(12,186	)
Capital expenditures		20,937		62,121			16,111		4,705			4,300			108,174

Three months ended September 30, 2010
Revenues	$	440,439	$	296,227		$	138,039	$	—		$	—		$	874,705
Income from operations		51,787		55,664			14,816		—			(23,920	)		98,347
Depreciation, depletion and amortization		49,005		24,435			18,940		—			477			92,857
Amortization of acquired sales contracts, net		10,038		—			—		—			—			10,038
Capital expenditures		8,164		16,910			20,703		—			3,848			49,625

Nine Months ended September 30, 2011
Revenues	$	1,178,537	$	1,336,581		$	513,388	$	28,633		$	—		$	3,057,139
Income (loss) from operations		121,119		224,561			95,218		(1,814	)		(147,401	)		291,683
Total assets		2,240,458		5,159,710			667,658		222,014			1,565,421			9,855,261
Depreciation, depletion and amortization		125,532		108,904			61,753		4,386			1,171			301,746
Amortization of acquired sales contracts, net		15,349		(20,145	)		—		43			—			(4,753	)
Capital expenditures		39,422		108,711			38,003		9,078			20,685			215,899

Nine months ended September 30, 2010
Revenues	$	1,170,353	$	777,619		$	402,902	$	—		$	—		$	2,350,874
Income from operations		101,525		147,336			41,122		—			(52,937	)		237,046
Total assets		2,304,277		701,670			677,968		—			1,150,871			4,834,786
Depreciation, depletion and amortization		138,059		72,190			57,700		—			1,186			269,135
Amortization of acquired sales contracts, net		26,005		—			—		—			—			26,005
Capital expenditures		12,614		41,519			54,507		—			112,943			221,583

A reconciliation of segment income from operations to consolidated income before income taxes follows:


		Three Months Ended September 30						Nine Months Ended September 30
		2011			2010			2011			2010
		(In thousands)						(In thousands)
Income from operations	$	92,266		$	98,347		$	291,683		$	237,046
Interest expense		(77,694	)		(37,698	)		(154,523	)		(107,906	)
Interest income		840			927			2,341			1,888
Bridge financing costs related to ICG		—			—			(49,490	)		—
Net loss resulting from early retirement of debt		(1,708	)		(6,776	)		(1,958	)		(6,776	)
Income before income taxes	$	13,704		$	54,800		$	88,053		$	124,252

- 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/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8981-108599

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8984-108599

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9054-108599

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9031-108599

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8924-108599

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8538-108599

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8906-108599

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9038-108599

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 29
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8864-108599

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8971-108599

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 26
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8844-108599

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8380-108599

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8595-108599

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8933-108599

+ Details

Supplemental Condensed Consolidating Financial Information

9 Months Ended

Sep. 30, 2011

Supplemental Condensed Consolidating Financial Information [Abstract]

Supplemental Condensed Consolidating Financial Information

19. Supplemental Condensed Consolidating Financial Information

Pursuant to the indentures governing Arch Coal, Inc.'s senior notes, certain wholly-owned subsidiaries of the Company have fully and unconditionally guaranteed the senior notes on a joint and several basis. The following tables present unaudited condensed consolidating financial information for (i) the Company, (ii) the issuer of the senior notes, (iii) the guarantors under the senior notes, and (iv) the entities which are not guarantors under the senior notes (Arch Western Resources, LLC and its subsidiaries, Arch Receivable Company, LLC and the Company's subsidiaries outside the U.S.):


Condensed Consolidating Statements of Income
Three Months Ended September 30, 2011
					(unaudited)
					Guarantor			Non-Guarantor
	Parent/Issuer				Subsidiaries			Subsidiaries			Eliminations			Consolidated
								(In thousands)
Revenues	$	–		$	651,326		$	547,347			$ –		$	1,198,673

Costs, expenses and other
Cost of sales		7,442			522,636			448,680			(25,908	)		952,850
Depreciation, depletion and amortization		718			83,775			38,533			–			123,026
Amortization of acquired sales contracts, net		–			(15,989	)		3,803			–			(12,186	)
Selling, general and administrative expenses		20,263			5,058			9,751			(1,796	)		33,276
Change in fair value of coal derivatives and coal
trading activities, net		–			8,360			–			–			8,360
Acquisition and transition costs related to ICG		4,694			–			–			–			4,694
Other operating (income) expense, net		(6,063	)		(30,509	)		5,255			27,704			(3,613	)
		27,054			573,331			506,022			-			1,106,407
Income from investment in subsidiaries		121,210			–			–			(121,210	)		–

Income from operations		94,156			77,995			41,325			(121,210	)		92,266

Interest expense, net:
Interest expense		(84,045	)		(942	)		(10,657	)		17,950			(77,694	)
Interest income		3,593			108			15,089			(17,950	)		840
		(80,452	)		(834	)		4,432			–			(76,854	)

Other non-operating expense
Net loss resulting from early retirement of debt		–			(1,708	)		-			–			(1,708	)
		–			(1,708	)		-			–			(1,708	)

Income before income taxes		13,704			75,453			45,757			(121,210	)		13,704
Benefit from income taxes		(5,583	)		–			–			–			(5,583	)

Net income		19,287			75,453			45,757			(121,210	)		19,287
Less: Net income attributable to noncontrolling
interest		(231	)		–			–			–			(231	)

Net income attributable to Arch Coal	$	19,056		$	75,453		$	45,757		$	(121,210	)	$	19,056


Condensed Consolidating Statements of Income
Three Months Ended September 30, 2010
(unaudited)
					Guarantor		Non-Guarantor
	Parent/Issuer				Subsidiaries		Subsidiaries				Eliminations			Consolidated
							(In thousands)

Revenues	$	–		$	324,507		$	550,198		$	–		$	874,705

Costs, expenses and other
Cost of sales		3,578			229,731			445,814			(27,270	)		651,853
Depreciation, depletion and amortization		794			52,302			39,761			–			92,857
Amortization of acquired sales contracts, net		–			–			10,038			–			10,038
Selling, general and administrative expenses		18,245			1,858			8,818			(1,922	)		26,999
Change in fair value of coal derivatives and
coal trading activities, net		–			1,832			–			–			1,832
Other operating (income) expense, net		(3,346	)		(35,107	)		2,040			29,192			(7,221	)
		19,271			250,616			506,471			–			776,358
Income from investment in subsidiaries		108,974			–			–			(108,974	)		–

Income from operations		89,703			73,891			43,727			(108,974	)		98,347

Interest expense, net:
Interest expense		(38,041	)		(745	)		(16,738	)		17,826			(37,698	)
Interest income		3,138			119			15,496			(17,826	)		927
		(34,903	)		(626	)		(1,242	)		–			(36,771	)

Other non-operating expense
Net loss resulting from early retirement of debt		–			–			(6,776	)		–			(6,776	)
		–			–			(6,776	)		–			(6,776	)

Income before income taxes		54,800			73,265			35,709			(108,974	)		54,800
Provision for income taxes		7,941						–			–			7,941

Net income		46,859			73,265			35,709			(108,974	)		46,859
Less: Net income attributable to
noncontrolling interest		(181	)		–			–			–			(181	)

Net income attributable to Arch Coal	$	46,678		$	73,265		$	35,709		$	(108,974	)	$	46,678


Condensed Consolidating Statements of Income
Nine Months Ended September 30, 2011
			(unaudited)

						Guarantor			Non-Guarantor
	Parent/Issuer					Subsidiaries			Subsidiaries			Eliminations			Consolidated
									(In thousands)
Revenues	$		–		$	1,409,755		$	1,647,384			$ –		$	3,057,139

Costs, expenses and other
Cost of sales			15,661			1,062,692			1,319,711			(75,940	)		2,322,124
Depreciation, depletion and amortization			2,050			181,059			118,637			–			301,746
Amortization of acquired sales contracts, net			–			(20,102	)		15,349			–			(4,753	)
Selling, general and administrative expenses			59,198			10,112			28,768			(5,328	)		92,750
Change in fair value of coal derivatives and
coal trading activities, net			–			9,248			–			–			9,248
Acquisition and transition costs related to ICG			53,360			–			–			–			53,360
Other operating (income) expense, net			(15,461	)		(87,210	)		12,384			81,268			(9,019	)
			114,808			1,155,799			1,494,849			-			2,765,456
Income from investment in subsidiaries			413,406			–			–			(413,406	)		–

Income from operations			298,598			253,956			152,535			(413,406	)		291,683

Interest expense, net:
Interest expense			(172,700	)		(3,793	)		(32,599	)		54,569			(154,523	)
Interest income			11,645			540			44,725			(54,569	)		2,341
			(161,055	)		(3,253	)		12,126			–			(152,182	)

Other non-operating expense
Bridge financing costs related to ICG			(49,490	)		-			-			-			(49,490	)
Net loss resulting from early retirement of
debt			–			(1,958	)		-			–			(1,958	)
			(49,490	)		(1,958	)		-			–			(51,448	)

Income before income taxes			88,053			248,745			164,661			(413,406	)		88,053
Provision for income taxes			5,103			–			–			–			5,103

Net income			82,950			248,745			164,661			(413,406	)		82,950
Less: Net income attributable to noncontrolling interest			(822	)		–			–			–			(822	)

Net income attributable to Arch Coal		$	82,128		$	248,745		$	164,661		$	(413,406	)	$	82,128


Condensed Consolidating Statements of Income
	Nine Months Ended September 30, 2010
		(unaudited)

					Guarantor			Non-Guarantor
	Parent/Issuer				Subsidiaries			Subsidiaries			Eliminations			Consolidated
								(In thousands)

Revenues	$	–		$	846,351		$	1,504,523		$	–		$	2,350,874

Costs, expenses and other
Cost of sales		8,554			591,692			1,239,893			(66,675	)		1,773,464
Depreciation, depletion and amortization		2,270			142,961			123,904			–			269,135
Amortization of acquired sales contracts, net		–			–			26,005			–			26,005
Selling, general and administrative expenses		60,139			5,500			29,226			(5,356	)		89,509
Change in fair value of coal derivatives and
coal trading activities, net		–			12,296			–			–			12,296
Gain on Knight Hawk transaction		–			(41,577	)		–			–			(41,577	)
Other operating (income) expense, net		(8,124	)		(84,031	)		5,120			72,031			(15,004	)
		62,839			626,841			1,424,148			–			2,113,828
Income from investment in subsidiaries		282,794			–			–			(282,794	)		–

Income from operations		219,955			219,510			80,375			(282,794	)		237,046

Interest expense, net:
Interest expense		(102,996	)		(2,104	)		(53,241	)		50,435			(107,906	)
Interest income		7,293			283			44,747			(50,435	)		1,888
		(95,703	)		(1,821	)		(8,494	)		–			(106,018	)

Other non-operating expense
Net loss resulting from early retirement of debt		–			–			(6,776	)		–			(6,776	)
		–			–			(6,776	)		–			(6,776	)

Income before income taxes		124,252			217,689			65,105			(282,794	)		124,252
Provision for income taxes		12,889			–			–			–			12,889

Net income		111,363			217,689			65,105			(282,794	)		111,363
Less: Net income attributable to
noncontrolling interest		(325	)		–			–			–			(325	)

Net income attributable to Arch Coal	$	111,038		$	217,689		$	65,105		$	(282,794	)	$	111,038


		Condensed Consolidating Balance Sheets
		September 30, 2011
					(unaudited)

					Guarantor		Non-Guarantor
		Parent/Issuer			Subsidiaries		Subsidiaries				Eliminations				Consolidated
							(In thousands)
Assets
Cash and cash equivalents	$	57,778		$	280			$	100,451		$–			$	158,509
Restricted cash		21,428			-				-		–				21,428
Receivables		63,111			130,884				233,855		(1,550	)			426,300
Inventories		–			173,564				172,767		–				346,331
Other		35,413			102,729				16,873		–				155,015
Total current assets		177,730			407,457				523,946		(1,550	)			1,107,583
Property, plant and equipment, net		13,685			6,234,786				1,454,809		–				7,703,280
Investment in subsidiaries		8,632,002			–				–		(8,632,002	)			–
Intercompany receivables		(2,243,557	)		813,061				1,430,496		–				–
Note receivable from Arch Western		225,000			-				-		(225,000	)			–
Other		456,885			574,038				13,475		–				1,044,398
Total other assets		7,070,330			1,387,099				1,443,971		(8,857,002	)			1,044,398

Total assets	$	7,261,745		$	8,029,342			$	3,422,726	$	(8,858,552	)	$		9,855,261

Liabilities and Stockholders' Equity
Accounts payable	$	33,646		$	151,826		$		107,974	$	–		$		293,446
Accrued expenses and other current
liabilities		108,442			132,785				145,854		(1,550	)			385,531
Current maturities of debt and short-term
borrowings		4,357			2,799				40,000		–				47,156
Total current liabilities		146,445			287,410				293,828		(1,550	)			726,133
Long-term debt		3,388,496			1,702				451,132						3,841,330
Note payable to Arch Coal		-			–				225,000		(225,000	)			-
Asset retirement obligations		548			107,002				308,327		–				415,877
Accrued pension benefits		7,057			(489	)			9,667		–				16,235
Accrued postretirement benefits other
than pension		15,276			50,241				23,303		–				88,820
Accrued workers' compensation		14,866			42,850				6,705		–				64,421
Deferred income taxes		(4,162	)		884,649				-		–				880,487
Other noncurrent liabilities		148,751			75,565				53,174		–				277,490
Total liabilities		3,717,277			1,448,930				1,371,136		(226,550	)			6,310,793
Redeemable noncontrolling interest		11,261			–				–		–				11,261

Stockholders' equity		3,533,207			6,580,412				2,051,590		(8,632,002	)			3,533,207
Total liabilities and stockholders'
equity	$	7,261,745		$	8,029,342		$		3,422,726	$	(8,858,552	)	$		9,855,261


Condensed Consolidating Balance Sheets
December 31, 2010
(unaudited)

					Guarantor		Non-Guarantor
		Parent/Issuer			Subsidiaries		Subsidiaries			Eliminations			Consolidated
							(In thousands)
Assets
Cash and cash equivalents	$	13,713			$	64	$	79,816	$	—		$	93,593
Receivables		31,458			12,740			210,075		(1,953	)		252,320
Inventories		—			85,196			150,420		—			235,616
Other		29,575			102,375			21,435		—			153,385
Total current assets		74,746			200,375			461,746		(1,953	)		734,914
Property, plant and equipment, net		9,817			1,800,578			1,498,497		—			3,308,892
Investment in subsidiaries		4,555,233				—		—		(4,555,233	)		—
Intercompany receivables		(1,807,902	)		508,624			1,299,278		—			—
Note receivable from Arch Western		225,000				—		—		(225,000	)		—
Other		481,345			344,698			10,920		—			836,963
Total other assets		3,453,676			853,322			1,310,198		(4,780,233	)		836,963
Total assets	$	3,538,239		$	2,854,275		$	3,270,441	$	(4,782,186	)	$	4,880,769

Liabilities and Stockholders' Equity
Accounts payable	$	10,753		$	65,793		$	121,670	$	—		$	198,216
Accrued expenses and other current liabilities		75,746			31,123			153,217		(1,953	)		258,133
Current maturities of debt and short-term
borrowings		14,093				—		56,904		—			70,997
Total current liabilities		100,592			96,916			331,791		(1,953	)		527,346
Long-term debt		1,087,126				—		451,618		—			1,538,744
Note payable to Arch Coal		—				—		225,000		(225,000	)		—
Asset retirement obligations		873			32,029			301,355		—			334,257
Accrued pension benefits		20,843				4,407		23,904		—			49,154
Accrued postretirement benefits other than
pension		14,284				—		23,509		—			37,793
Accrued workers' compensation		15,383			13,805			6,102		—			35,290
Other noncurrent liabilities		51,187			22,135			36,912		—			110,234
Total liabilities		1,290,288			169,292			1,400,191		(226,953	)		2,632,818
Redeemable noncontrolling interest		10,444				—		—		—			10,444
Stockholders' equity		2,237,507			2,684,983			1,870,250		(4,555,233	)		2,237,507
Total liabilities and stockholders' equity	$	3,538,239		$	2,854,275		$	3,270,441	$	(4,782,186	)	$	4,880,769


Condensed Consolidating Statements of Cash Flows
Nine Months Ended September 30, 2011
(unaudited)

					Guarantor			Non-Guarantor
		Parent/Issuer			Subsidiaries			Subsidiaries			Eliminations			Consolidated
								(In thousands)
Cash provided by (used in) operating
activities	$	(444,664	)	$	613,179		$	302,852		$	-		$	471,367
Investing Activities
Acquisition of ICG, net of cash acquired		(2,894,339	)		-			-			-			(2,894,339	)
Increase in restricted cash		(5,939	)		-			-			-			(5,939	)
Capital expenditures		(5,137	)		(135,640	)		(75,122	)		-			(215,899	)
Proceeds from dispositions of property, plant
and equipment		–			25,010			123			-			25,133
Purchases of investments and advances to
affiliates		(777,341	)		(29,872	)		–			750,386			(56,827	)
Additions to prepaid royalties		–			(22,163	)		(3,972	)		–			(26,135	)
Cash used in investing activities		(3,682,756	)		(162,665	)		(78,971	)		750,386			(3,174,006	)

Financing Activities

Proceeds from the issuance of senior notes		2,000,000			–			-			-			2,000,000
Proceeds from the issuance of common stock,
net		1,267,776			–			-			-			1,267,776
Contributions from parent		-			750,386			-			(750,386	)		–
Payments to retire debt		-			(604,096	)		-			-			(604,096	)
Net increase (decrease) in borrowings under
lines of credit and commercial paper program		340,000			–			(56,904	)		-			283,096
Net payments on other debt		(8,792	)		–			–			-			(8,792	)
Debt financing costs		(114,563	)		–			(24	)		-			(114,587	)
Dividends paid		(57,470	)		–			–			-			(57,470	)
Issuance of common stock under incentive
plans		1,628			–			–			-			1,628
Transactions with affiliates, net		742,906			(596,588	)		(146,318	)		-			–
Cash provided by (used in) financing
activities		4,171,485			(450,298	)		(203,246	)		(750,386	)		2,767,555
Increase in cash and cash equivalents		44,065			216			20,635			-			64,916
Cash and cash equivalents, beginning of
period		13,713			64			79,816			-			93,593
Cash and cash equivalents, end of period	$	57,778		$	280		$	100,451		$	-		$	158,509


Condensed Consolidating Statements of Cash Flows
Nine Months Ended September 30, 2010
					(unaudited)

					Guarantor			Non-Guarantor
		Parent/Issuer			Subsidiaries			Subsidiaries			Consolidated
					(In thousands)
Cash provided by (used in) operating
activities	$	(224,066	)	$	404,836		$	275,910		$	456,680
Investing Activities
Capital expenditures		(3,942	)		(141,825	)		(75,816	)		(221,583	)
Proceeds from dispositions of property, plant and
equipment		–			178			74			252
Purchases of investments and advances to affiliates		(12,671	)		(4,069	)		–			(16,740	)
Additions to prepaid royalties		–			(20,880	)		(2,835	)		(23,715	)
Cash used in investing activities		(16,613	)		(166,596	)		(78,577	)		(261,786	)

Financing Activities
Proceeds from the issuance of senior notes		500,000			–			–			500,000
Payments to retire debt		–			–			(505,627	)		(505,627	)
Net increase (decrease) in borrowings under lines of
credit and commercial paper program		(120,000	)		–			1,663			(118,337	)
Net payments on other debt		(9,794	)		–			–			(9,794	)
Debt financing costs		(11,901	)		–			(729	)		(12,630	)
Dividends paid		(47,121	)		–			–			(47,121	)
Issuance of common stock under incentive plans		339			–			–			339
Contribution from noncontrolling interest		–			–			891			891
Transactions with affiliates, net		(123,309	)		(238,252	)		361,561			–
Cash provided by (used in) financing
activities		188,214			(238,252	)		(142,241	)		(192,279	)
Increase (decrease) in cash and cash equivalents		(52,465	)		(12	)		55,092			2,615
Cash and cash equivalents, beginning of
period		54,255			64			6,819			61,138
Cash and cash equivalents, end of period	$	1,790		$	52		$	61,911		$	63,753

Business Combination (Tables)

9 Months Ended

Sep. 30, 2011

Business Combination [Abstract]

Summary Of Purchase Price Allocation


		(In millions)
Consideration paid, net of cash acquired	$	2,894.4
Recognized amounts of net tangible and intangible assets acquired and liabilities assumed:
Restricted cash		15.5
Receivables		114.2
Inventories		87.0
Net property, plant and equipment, including mineral rights		4,510.6
Goodwill		425.0
Other assets		49.2
Accounts payable		(82.6	)
Other accrued expenses and current liabilities		(61.5	)
Debt		(604.8	)
Litigation accrual		(106.0	)
Accrued postretirement benefits		(47.7	)
Asset retirement obligation		(80.4	)
Coal supply agreements, net		(98.8	)
Deferred income taxes, net		(1,189.9	)
Other		(35.4	)
Net tangible and intangible assets acquired	$	2,894.4

Adjustments to Purchase Price and Provisional Fair Values


		(In millions)
Inventories		9.5
Net property, plant and equipment, including mineral rights		(5.8	)
Coal supply agreements, net		(21.2	)
Other		1.5
Purchase price adjustment – cash received	$	(16.0	)

Summary Of Unaudited Pro Forma


	Three Months Ended September 30				Nine Months Ended September 30
	2011		2010		2011		2010
				(In millions)
Total revenues
As reported	$	1,198.7	$	874.7	$	3,057.1	$	2,350.9
Pro forma	$	1,198.7	$	1,176.9	$	3,596.8	$	3,212.6

Income (loss) before income taxes
As reported	$	13.7	$	54.8	$	88.1	$	124.3
Pro forma	$	22.3	$	47.5	$	72.6	$	(66.9	)

Schedule of Business Acquisition, Integration, Restructuring and Other Related Costs


		Three Months Ended		Nine Months Ended
		September 30, 2011		September 30, 2011
		(In thousands)
Costs of completing the acquisition - Arch	$	1,717	$	29,569
Costs of completing the acquisition - ICG		—		23,503
Severance costs		2,977		16,475
Write off of acquired assets		—		7,316
Bridge financing fees		—		49,490
	$	4,694	$	126,353

- Definition

Tabular disclosure of pro forma results of operations for a material business acquisition or series of individually immaterial business acquisitions that are material in the aggregate.

+ References + Details

Debt (Tables)

9 Months Ended

Sep. 30, 2011

Debt [Abstract]

Debt


		September 30,		December 31,
		2011		2010
		(In thousands)
Commercial paper	$	—	$	56,904
Indebtedness to banks under credit facilities		340,000		—
6.75% senior notes ($450.0 million face value) due July 1, 2013		451,132		451,618
8.75% senior notes ($600.0 million face value) due August 1, 2016		588,496		587,126
7.00% senior notes due June 15, 2019 at par		1,000,000		—
7.25% senior notes due October 1, 2020 at par		500,000		500,000
7.25% senior notes due June 15, 2021 at par		1,000,000		—
Other		8,858		14,093
		3,888,486		1,609,741
Less current maturities of debt and short-term borrowings		47,156		70,997
Long-term debt	$	3,841,330	$	1,538,744

Acquired Sales Contracts (Tables)

9 Months Ended

Sep. 30, 2011

Acquired Sales Contracts [Abstract]

Schedule Of Acquired Sales Contract


		September 30, 2011						December 31, 2010
		Assets		Liabilities				Assets			Liabilities
		(In thousands)						(In thousands)
Acquired fair value	$	145,213		$	170,341		$	114,453		$	40,654
Accumulated amortization		(105,845	)		(42,877	)		(82,376	)		(14,613	)
Total	$	39,368		$	127,464		$	32,077		$	26,041
Net total				$	88,096		$	6,036

Balance Sheet classification:
Other current	$	23,474		$	58,049		$	25,063		$	5,615
Other noncurrent	$	15,894		$	69,415		$	7,014		$	20,426

Investments (Tables)

9 Months Ended

Sep. 30, 2011

Investments [Abstract]

Schedule Of Equity Method Investments


		Knight Hawk			DKRW			DTA			Tenaska			Millennium			Tongue River		Total
											(In thousands)
Balance at December 31, 2010	$	131,250		$	21,961		$	14,472		$	9,768		$	—		$	—	$	177,451
Investments in affiliates		—			—			—			5,500			25,000			12,989		43,489
Advances to (distributions from) affiliates, net		(11,450	)		—			4,394			—			1,900			—		(5,156	)
Equity in comprehensive income (loss)		15,807			(1,631	)		(3,713	)		(2	)		(1,561	)		—		8,900
Balance at September 30, 2011	$	135,607		$	20,330		$	15,153		$	15,266		$	25,339		$	12,989	$	224,684

Notes receivable from investees:
Balance at December 31, 2010	$	1,700		$	18,100		$	—		$	4,100		$	—		$	—	$	23,900
Balance at September 30, 2011		—			28,417			—			4,777			—			—		33,194

Derivatives (Tables)

9 Months Ended

Sep. 30, 2011

Derivatives [Abstract]

Disclosure Of Fair Value Of Derivatives

Fair Value of Derivatives (in thousands)


		September 30, 2011								December 31, 2010
		Asset			Liability					Asset			Liability
		Derivative			Derivative					Derivative			Derivative
Derivatives Designated as Hedging
Instruments
Heating oil – diesel purchases	$	9,352		$	—				$	13,475		$	—
Coal		2,708			(1,270	)				2,009			(2,350	)
Total		12,060			(1,270	)				15,484			(2,350	)
Derivatives Not Designated as Hedging
Instruments
Heating oil – fuel surcharges		2,202			—					—			—
Coal — held for trading purposes		10,862			(10,365	)				34,445			(24,087	)
Coal		1,812			(6,976	)				1,139			(912	)
Total		14,876			(17,341	)				35,584			(24,999	)
Total derivatives		26,936			(18,611	)				51,068			(27,349	)
Effect of counterparty netting		(12,787	)		12,787					(22,402	)		22,402
Net derivatives as classified in the
balance sheets	$	14,149		$	(5,824	)	$	8,325	$	28,666		$	(4,947	)	$	23,719

Net derivatives as reflected on the balance sheets


			September 30,			December 31,
			2011			2010
Heating oil	Other current assets	$	11,554		$	13,475
Coal	Coal derivative assets		2,595			15,191
	Coal derivative liabilities		(5,824	)		(4,947	)
		$	8,325		$	23,719

Effects Of Derivatives On Measures Of Financial Performance

Three Months Ended September 30 (in thousands)


	Gain (Loss) Recognized in OCI (Effective Portion)						Gains (Losses) Reclassified from OCI into Income (Effective Portion)							Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)



Derivatives used in
Cash Flow Hedging
Relationships	2011			2010			2011			2010				2011		2010
Heating oil – diesel purchases	$	(6,386	)	$	3,052		$	5,122	(2)	$	93		(2)	$	—	$	—
Coal sales		1,820			1,500			466	(1)		(226	)	(1)		—		—
Coal purchases		(1,274	)		(2,535	)		—	(2)		(866	)	(2)		—		—
Totals	$	(5,840	)	$	2,017		$	5,588		$	(999	)		$	—	$	—


Derivatives Not Designated as	Gain (Loss)
Hedging Instruments	2011				2010
Coal — unrealized	$	(6,131	)	(3)	$	(993	)	(3)
Coal — realized	$	166		(4)	$	1,079		(4)
Heating oil — fuel surcharges — unrealized	$	(2,501	)	(4)	$	—		(4)

Location in Statement of Income:

(1) Revenues

(2) Cost of sales

(3) Change in fair value of coal derivatives and coal trading activities, net

(4) Other operating income, net

Nine Months Ended September 30 (in thousands)


		Gain (Loss) Recognized in OCI (Effective Portion)						Gains (Losses) Reclassified from OCI into Income (Effective Portion)							Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)



Derivatives used in
Cash Flow Hedging
Relationships		2011			2010			2011			2010				2011				2010
Heating oil– diesel purchases	$	1,535		$	(5,508	)	$	14,946	(2)	$	(211	)	(2)	$	—			$	—
Coal sales		4,570			(6,138	)		790	(1)		(1,556	)	(1)		—				—
Coal purchases		(2,053	)		5,534			—	(2)		(1,202	)	(2)		—				—
Totals	$	4,052		$	(6,112	)	$	15,736		$	(2,969	)		$	—			$	—

Derivatives Not Designated as														Gain (Loss)
Hedging Instruments														2011				2010
Coal — unrealized														$	(7,550	)	(3)	$	(9,381	)	(3)
Coal — realized														$	313		(4)	$	3,931		(4)
Heating oil — fuel surcharges — unrealized														$	(2,501	)	(4)	$	—		(4)

Location in Statement of Income:

(1) Revenues

(2) Cost of sales

(3) Change in fair value of coal derivatives and coal trading activities, net

(4) Other operating income, net

- Definition

Tabular disclosure of the location and amount of gains and losses reported in the statement of financial performance, or when applicable, the statement of financial position. For example, (a) gains and losses recognized in the income statement on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges and (b) gains and losses initially recognized in other comprehensive income on derivative instruments designated and qualifying as cash flow hedges.

+ References + Details

Inventories (Tables)

9 Months Ended

Sep. 30, 2011

Inventories [Abstract]

Inventories


Inventories consist of the following:
		September 30,		December 31,
		2011		2010
		(In thousands)
Coal	$	180,988	$	115,647
Repair parts and supplies, net of allowance		165,343		119,969
	$	346,331	$	235,616

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2011

Fair Value Measurements [Abstract]

Summary Of Financial Assets And Liabilities Accounted For At Fair Value


	Fair Value at September 30, 2011
	Total		Level 1		Level 2			Level 3
				(In thousands)
Assets:
Investments in equity securities	$	5,351	$	5,351	$	—		$	—
Derivatives		14,149		1,018		2,695			10,436
Total assets	$	19,500	$	6,369	$	2,695		$	10,436
Liabilities:
Derivatives	$	5,824	$	—	$	(415	)	$	6,239

Summary Of Change In The Fair Values Of Financial Instruments Categorized As Level 3


	Three Months Ended September 30, 2011			Nine Months Ended September 30, 2011
	Three Months Ended September 30, 2011			Nine Months Ended September 30, 2011
	(In thousands)
Balance, beginning of period	$	10,474		$	9,183
Realized and unrealized losses recognized in earnings, net		(8,016	)		(15,140	)
Realized and unrealized losses recognized in other comprehensive income, net		(6,702	)		(3,227	)
Purchases		9,935			20,407
Issuances		—			(2,160	)
Settlements		(1,494	)		(4,866	)
Balance, end of period	$	4,197		$	4,197

- Definition

Tabular disclosure of the fair value measurement of assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income, and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issuances, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset.

+ References + Details

- Definition

Tabular disclosure of the fair value measurement of assets and liabilities which includes [financial] instruments measured at fair value that are classified in stockholders' equity. Such assets and liabilities may be measured on a recurring or nonrecurring basis. The disclosures which may be required or desired include: (1) for assets and liabilities measured on a recurring basis, disclosure may include: (a) the fair value measurements at the reporting date; (b) the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3); (c) for fair value measurements using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (i) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (ii) purchases, sales, issuances, and settlements (net); (iii) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs); (d) the amount of the total gains or losses for the period in subparagraph (c) (i) above included in earnings (or changes in net assets) that are attributable to the change in unrealized gains or losses relating to those assets and liabilities still held at the reporting date and a description of where those unrealized gains or losses are reported in the statement of income (or activities); (e) the valuation technique(s) used to measure fair value and a discussion of changes in valuation techniques, if any, during the period and (2) for assets and liabilities that are measured at fair value on a nonrecurring basis (for example, impaired assets) disclosure may include, in addition to (a) above: (a) the reasons for the fair value measurements recorded; (b) the same as (b) above; (c) for fair value measurements using significant unobservable inputs (Level 3), a description of the inputs and the information used to develop the inputs; and (d) the valuation technique(s) used to measure fair value and a discussion of changes, if any, in the valuation technique(s) used to measure similar assets and/or liabilities in prior periods. Where the quoted price in an active market for the identical liability is not available, the Level 1 input is the quoted price of an identical liability when traded as an asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 33
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 6
-Footnote 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19190-110258

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19279-110258

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19296-110258

+ Details

Workers' Compensation Expense (Tables)

9 Months Ended

Sep. 30, 2011

Workers' Compensation Expense [Abstract]

Workers' Compensation Expense


	Three Months Ended September 30						Nine Months Ended September 30
	2011			2010			2011			2010
	(In thousands)						(In thousands)
Self-insured occupational disease benefits:
Service cost	$	807		$	182		$	1,246		$	545
Interest cost		619			169			1,177			507
Net amortization		(109	)		(465	)		(370	)		(1,395	)
Total occupational disease		1,317			(114	)		2,053			(343	)
Traumatic injury claims and assessments		5,207			2,642			10,856			6,562
Total workers' compensation expense	$	6,524		$	2,528		$	12,909		$	6,219

Employee Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2011

Employee Benefit Plans [Abstract]

Pension Benefit Costs


	Three Months Ended September 30						Nine Months Ended September 30
	2011			2010			2011			2010
	(In thousands)						(In thousands)
Service cost	$	4,122		$	3,967		$	12,367		$	11,902
Interest cost		4,063			3,955			12,190			11,866
Expected return on plan assets		(5,453	)		(4,848	)		(16,359	)		(14,544	)
Amortization of prior service cost (credit)		(47	)		44			(142	)		130
Amortization of other actuarial losses		2,187			1,782			6,561			5,348
Net benefit cost	$	4,872		$	4,900		$	14,617		$	14,702

Other Postretirement Benefit Costs


	Three Months Ended September 30						Nine Months Ended September 30
	2011			2010			2011			2010
	(In thousands)						(In thousands)
Service cost	$	1,493		$	378		$	2,416		$	1,132
Interest cost		1,125			520			2,152			1,562
Amortization of prior service credits		(636	)		(591	)		(1,773	)		(1,773	)
Amortization of other actuarial gains		(775	)		(729	)		(2,325	)		(2,188	)
Net benefit cost (credit)	$	1,207		$	(422	)	$	470		$	(1,267	)

- Definition

Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5, 6, 7
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 4, 7, 16, 20, 21
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=6930749&loc=d3e4179-114921

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2410-114920

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2439-114920

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2417-114920

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Comprehensive Income (Tables)

9 Months Ended

Sep. 30, 2011

Comprehensive Income [Abstract]

Components Of Comprehensive Income


		Three Months Ended September 30					Nine Months Ended September 30
	2011			2010		2011			2010
	(In thousands)					(In thousands)
Net income attributable to Arch Coal, Inc.	$	19,056		$	46,678	$	82,128		$	111,038
Other comprehensive income, net of income taxes:
Pension, postretirement and other post-employment benefits,
reclassifications into net income		388			28		1,254			84
Unrealized gains (losses) on available-for-sale securities		(569	)		738		(1,256	)		(178	)
Unrealized gains and losses on derivatives, net of
reclassifications into net income:
Unrealized gains (losses) on derivatives		(3,671	)		1,200		2,703			(3,889	)
Reclassifications of (gains) losses into net income		(3,575	)		639		(10,059	)		1,856
Total comprehensive income	$	11,629		$	49,283	$	74,770		$	108,911

Earnings per Common Share (Tables)

9 Months Ended

Sep. 30, 2011

Earnings Per Common Share

Earnings per Share


	Three Months Ended September 30		Nine Months Ended September 30
	2011	2010	2011	2010
	(In thousands)		(In thousands)
Weighted average shares outstanding:
Basic weighted average shares outstanding	211,337	162,391	182,898	162,384
Effect of common stock equivalents under incentive plans	637	783	952	744
Diluted weighted average shares outstanding	211,974	163,174	183,850	163,128

Segment Information (Tables)

9 Months Ended

Sep. 30, 2011

Segment Information [Abstract]

Schedule Of Operating Segment Results


									Other			Corporate,
									Operating			Other and
		PRB		APP			WBIT		Segments			Eliminations			Consolidated
	(In thousands)
Three months ended September 30, 2011
Revenues	$	394,012	$	611,403		$	168,795	$	24,463		$	—		$	1,198,673
Income (loss) from operations		38,630		77,511			24,653		(1,713	)		(46,815	)		92,266
Depreciation, depletion and amortization		42,676		59,576			19,125		3,781			(2,132	)		123,026
Amortization of acquired sales contracts, net		3,802		(16,022	)		—		34			—			(12,186	)
Capital expenditures		20,937		62,121			16,111		4,705			4,300			108,174

Three months ended September 30, 2010
Revenues	$	440,439	$	296,227		$	138,039	$	—		$	—		$	874,705
Income from operations		51,787		55,664			14,816		—			(23,920	)		98,347
Depreciation, depletion and amortization		49,005		24,435			18,940		—			477			92,857
Amortization of acquired sales contracts, net		10,038		—			—		—			—			10,038
Capital expenditures		8,164		16,910			20,703		—			3,848			49,625

Nine Months ended September 30, 2011
Revenues	$	1,178,537	$	1,336,581		$	513,388	$	28,633		$	—		$	3,057,139
Income (loss) from operations		121,119		224,561			95,218		(1,814	)		(147,401	)		291,683
Total assets		2,240,458		5,159,710			667,658		222,014			1,565,421			9,855,261
Depreciation, depletion and amortization		125,532		108,904			61,753		4,386			1,171			301,746
Amortization of acquired sales contracts, net		15,349		(20,145	)		—		43			—			(4,753	)
Capital expenditures		39,422		108,711			38,003		9,078			20,685			215,899

Nine months ended September 30, 2010
Revenues	$	1,170,353	$	777,619		$	402,902	$	—		$	—		$	2,350,874
Income from operations		101,525		147,336			41,122		—			(52,937	)		237,046
Total assets		2,304,277		701,670			677,968		—			1,150,871			4,834,786
Depreciation, depletion and amortization		138,059		72,190			57,700		—			1,186			269,135
Amortization of acquired sales contracts, net		26,005		—			—		—			—			26,005
Capital expenditures		12,614		41,519			54,507		—			112,943			221,583

Reconciliation Statement Of Segment Income From Operations To Consolidated Income Before Income Taxes


		Three Months Ended September 30						Nine Months Ended September 30
		2011			2010			2011			2010
		(In thousands)						(In thousands)
Income from operations	$	92,266		$	98,347		$	291,683		$	237,046
Interest expense		(77,694	)		(37,698	)		(154,523	)		(107,906	)
Interest income		840			927			2,341			1,888
Bridge financing costs related to ICG		—			—			(49,490	)		—
Net loss resulting from early retirement of debt		(1,708	)		(6,776	)		(1,958	)		(6,776	)
Income before income taxes	$	13,704		$	54,800		$	88,053		$	124,252

- Definition

Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.

+ References + Details

Supplemental Condensed Consolidating Financial Information (Tables)

9 Months Ended

Sep. 30, 2011

Supplemental Condensed Consolidating Financial Information [Abstract]

Schedule Of Condensed Consolidating Statements Of Income


Condensed Consolidating Statements of Income
Three Months Ended September 30, 2011
					(unaudited)
					Guarantor			Non-Guarantor
	Parent/Issuer				Subsidiaries			Subsidiaries			Eliminations			Consolidated
								(In thousands)
Revenues	$	–		$	651,326		$	547,347			$ –		$	1,198,673

Costs, expenses and other
Cost of sales		7,442			522,636			448,680			(25,908	)		952,850
Depreciation, depletion and amortization		718			83,775			38,533			–			123,026
Amortization of acquired sales contracts, net		–			(15,989	)		3,803			–			(12,186	)
Selling, general and administrative expenses		20,263			5,058			9,751			(1,796	)		33,276
Change in fair value of coal derivatives and coal
trading activities, net		–			8,360			–			–			8,360
Acquisition and transition costs related to ICG		4,694			–			–			–			4,694
Other operating (income) expense, net		(6,063	)		(30,509	)		5,255			27,704			(3,613	)
		27,054			573,331			506,022			-			1,106,407
Income from investment in subsidiaries		121,210			–			–			(121,210	)		–

Income from operations		94,156			77,995			41,325			(121,210	)		92,266

Interest expense, net:
Interest expense		(84,045	)		(942	)		(10,657	)		17,950			(77,694	)
Interest income		3,593			108			15,089			(17,950	)		840
		(80,452	)		(834	)		4,432			–			(76,854	)

Other non-operating expense
Net loss resulting from early retirement of debt		–			(1,708	)		-			–			(1,708	)
		–			(1,708	)		-			–			(1,708	)

Income before income taxes		13,704			75,453			45,757			(121,210	)		13,704
Benefit from income taxes		(5,583	)		–			–			–			(5,583	)

Net income		19,287			75,453			45,757			(121,210	)		19,287
Less: Net income attributable to noncontrolling
interest		(231	)		–			–			–			(231	)

Net income attributable to Arch Coal	$	19,056		$	75,453		$	45,757		$	(121,210	)	$	19,056


Condensed Consolidating Statements of Income
Three Months Ended September 30, 2010
(unaudited)
					Guarantor		Non-Guarantor
	Parent/Issuer				Subsidiaries		Subsidiaries				Eliminations			Consolidated
							(In thousands)

Revenues	$	–		$	324,507		$	550,198		$	–		$	874,705

Costs, expenses and other
Cost of sales		3,578			229,731			445,814			(27,270	)		651,853
Depreciation, depletion and amortization		794			52,302			39,761			–			92,857
Amortization of acquired sales contracts, net		–			–			10,038			–			10,038
Selling, general and administrative expenses		18,245			1,858			8,818			(1,922	)		26,999
Change in fair value of coal derivatives and
coal trading activities, net		–			1,832			–			–			1,832
Other operating (income) expense, net		(3,346	)		(35,107	)		2,040			29,192			(7,221	)
		19,271			250,616			506,471			–			776,358
Income from investment in subsidiaries		108,974			–			–			(108,974	)		–

Income from operations		89,703			73,891			43,727			(108,974	)		98,347

Interest expense, net:
Interest expense		(38,041	)		(745	)		(16,738	)		17,826			(37,698	)
Interest income		3,138			119			15,496			(17,826	)		927
		(34,903	)		(626	)		(1,242	)		–			(36,771	)

Other non-operating expense
Net loss resulting from early retirement of debt		–			–			(6,776	)		–			(6,776	)
		–			–			(6,776	)		–			(6,776	)

Income before income taxes		54,800			73,265			35,709			(108,974	)		54,800
Provision for income taxes		7,941						–			–			7,941

Net income		46,859			73,265			35,709			(108,974	)		46,859
Less: Net income attributable to
noncontrolling interest		(181	)		–			–			–			(181	)

Net income attributable to Arch Coal	$	46,678		$	73,265		$	35,709		$	(108,974	)	$	46,678


Condensed Consolidating Statements of Income
Nine Months Ended September 30, 2011
			(unaudited)

						Guarantor			Non-Guarantor
	Parent/Issuer					Subsidiaries			Subsidiaries			Eliminations			Consolidated
									(In thousands)
Revenues	$		–		$	1,409,755		$	1,647,384			$ –		$	3,057,139

Costs, expenses and other
Cost of sales			15,661			1,062,692			1,319,711			(75,940	)		2,322,124
Depreciation, depletion and amortization			2,050			181,059			118,637			–			301,746
Amortization of acquired sales contracts, net			–			(20,102	)		15,349			–			(4,753	)
Selling, general and administrative expenses			59,198			10,112			28,768			(5,328	)		92,750
Change in fair value of coal derivatives and
coal trading activities, net			–			9,248			–			–			9,248
Acquisition and transition costs related to ICG			53,360			–			–			–			53,360
Other operating (income) expense, net			(15,461	)		(87,210	)		12,384			81,268			(9,019	)
			114,808			1,155,799			1,494,849			-			2,765,456
Income from investment in subsidiaries			413,406			–			–			(413,406	)		–

Income from operations			298,598			253,956			152,535			(413,406	)		291,683

Interest expense, net:
Interest expense			(172,700	)		(3,793	)		(32,599	)		54,569			(154,523	)
Interest income			11,645			540			44,725			(54,569	)		2,341
			(161,055	)		(3,253	)		12,126			–			(152,182	)

Other non-operating expense
Bridge financing costs related to ICG			(49,490	)		-			-			-			(49,490	)
Net loss resulting from early retirement of
debt			–			(1,958	)		-			–			(1,958	)
			(49,490	)		(1,958	)		-			–			(51,448	)

Income before income taxes			88,053			248,745			164,661			(413,406	)		88,053
Provision for income taxes			5,103			–			–			–			5,103

Net income			82,950			248,745			164,661			(413,406	)		82,950
Less: Net income attributable to noncontrolling
interest			(822	)		–			–			–			(822	)

Net income attributable to Arch Coal		$	82,128		$	248,745		$	164,661		$	(413,406	)	$	82,128


Condensed Consolidating Statements of Income
	Nine Months Ended September 30, 2010
		(unaudited)

					Guarantor			Non-Guarantor
	Parent/Issuer				Subsidiaries			Subsidiaries			Eliminations			Consolidated
								(In thousands)

Revenues	$	–		$	846,351		$	1,504,523		$	–		$	2,350,874

Costs, expenses and other
Cost of sales		8,554			591,692			1,239,893			(66,675	)		1,773,464
Depreciation, depletion and amortization		2,270			142,961			123,904			–			269,135
Amortization of acquired sales contracts, net		–			–			26,005			–			26,005
Selling, general and administrative expenses		60,139			5,500			29,226			(5,356	)		89,509
Change in fair value of coal derivatives and
coal trading activities, net		–			12,296			–			–			12,296
Gain on Knight Hawk transaction		–			(41,577	)		–			–			(41,577	)
Other operating (income) expense, net		(8,124	)		(84,031	)		5,120			72,031			(15,004	)
		62,839			626,841			1,424,148			–			2,113,828
Income from investment in subsidiaries		282,794			–			–			(282,794	)		–

Income from operations		219,955			219,510			80,375			(282,794	)		237,046

Interest expense, net:
Interest expense		(102,996	)		(2,104	)		(53,241	)		50,435			(107,906	)
Interest income		7,293			283			44,747			(50,435	)		1,888
		(95,703	)		(1,821	)		(8,494	)		–			(106,018	)

Other non-operating expense
Net loss resulting from early retirement of debt		–			–			(6,776	)		–			(6,776	)
		–			–			(6,776	)		–			(6,776	)

Income before income taxes		124,252			217,689			65,105			(282,794	)		124,252
Provision for income taxes		12,889			–			–			–			12,889

Net income		111,363			217,689			65,105			(282,794	)		111,363
Less: Net income attributable to
noncontrolling interest		(325	)		–			–			–			(325	)

Net income attributable to Arch Coal	$	111,038		$	217,689		$	65,105		$	(282,794	)	$	111,038

Schedule Of Condensed Consolidating Balance Sheets


Condensed Consolidating Balance Sheets
		September 30, 2011
					(unaudited)

					Guarantor		Non-Guarantor
		Parent/Issuer			Subsidiaries		Subsidiaries				Eliminations				Consolidated
							(In thousands)
Assets
Cash and cash equivalents	$	57,778		$	280			$	100,451		$–			$	158,509
Restricted cash		21,428			-				-		–				21,428
Receivables		63,111			130,884				233,855		(1,550	)			426,300
Inventories		–			173,564				172,767		–				346,331
Other		35,413			102,729				16,873		–				155,015
Total current assets		177,730			407,457				523,946		(1,550	)			1,107,583
Property, plant and equipment, net		13,685			6,234,786				1,454,809		–				7,703,280
Investment in subsidiaries		8,632,002			–				–		(8,632,002	)			–
Intercompany receivables		(2,243,557	)		813,061				1,430,496		–				–
Note receivable from Arch Western		225,000			-				-		(225,000	)			–
Other		456,885			574,038				13,475		–				1,044,398
Total other assets		7,070,330			1,387,099				1,443,971		(8,857,002	)			1,044,398

Total assets	$	7,261,745		$	8,029,342			$	3,422,726	$	(8,858,552	)	$		9,855,261

Liabilities and Stockholders' Equity
Accounts payable	$	33,646		$	151,826		$		107,974	$	–		$		293,446
Accrued expenses and other current
liabilities		108,442			132,785				145,854		(1,550	)			385,531
Current maturities of debt and short-term
borrowings		4,357			2,799				40,000		–				47,156
Total current liabilities		146,445			287,410				293,828		(1,550	)			726,133
Long-term debt		3,388,496			1,702				451,132						3,841,330
Note payable to Arch Coal		-			–				225,000		(225,000	)			-
Asset retirement obligations		548			107,002				308,327		–				415,877
Accrued pension benefits		7,057			(489	)			9,667		–				16,235
Accrued postretirement benefits other
than pension		15,276			50,241				23,303		–				88,820
Accrued workers' compensation		14,866			42,850				6,705		–				64,421
Deferred income taxes		(4,162	)		884,649				-		–				880,487
Other noncurrent liabilities		148,751			75,565				53,174		–				277,490
Total liabilities		3,717,277			1,448,930				1,371,136		(226,550	)			6,310,793
Redeemable noncontrolling interest		11,261			–				–		–				11,261

Stockholders' equity		3,533,207			6,580,412				2,051,590		(8,632,002	)			3,533,207
Total liabilities and stockholders'
equity	$	7,261,745		$	8,029,342		$		3,422,726	$	(8,858,552	)	$		9,855,261


Condensed Consolidating Balance Sheets
December 31, 2010
(unaudited)

					Guarantor		Non-Guarantor
		Parent/Issuer			Subsidiaries		Subsidiaries			Eliminations			Consolidated
							(In thousands)
Assets
Cash and cash equivalents	$	13,713			$	64	$	79,816	$	—		$	93,593
Receivables		31,458			12,740			210,075		(1,953	)		252,320
Inventories		—			85,196			150,420		—			235,616
Other		29,575			102,375			21,435		—			153,385
Total current assets		74,746			200,375			461,746		(1,953	)		734,914
Property, plant and equipment, net		9,817			1,800,578			1,498,497		—			3,308,892
Investment in subsidiaries		4,555,233				—		—		(4,555,233	)		—
Intercompany receivables		(1,807,902	)		508,624			1,299,278		—			—
Note receivable from Arch Western		225,000				—		—		(225,000	)		—
Other		481,345			344,698			10,920		—			836,963
Total other assets		3,453,676			853,322			1,310,198		(4,780,233	)		836,963
Total assets	$	3,538,239		$	2,854,275		$	3,270,441	$	(4,782,186	)	$	4,880,769

Liabilities and Stockholders' Equity
Accounts payable	$	10,753		$	65,793		$	121,670	$	—		$	198,216
Accrued expenses and other current liabilities		75,746			31,123			153,217		(1,953	)		258,133
Current maturities of debt and short-term
borrowings		14,093				—		56,904		—			70,997
Total current liabilities		100,592			96,916			331,791		(1,953	)		527,346
Long-term debt		1,087,126				—		451,618		—			1,538,744
Note payable to Arch Coal		—				—		225,000		(225,000	)		—
Asset retirement obligations		873			32,029			301,355		—			334,257
Accrued pension benefits		20,843				4,407		23,904		—			49,154
Accrued postretirement benefits other than
pension		14,284				—		23,509		—			37,793
Accrued workers' compensation		15,383			13,805			6,102		—			35,290
Other noncurrent liabilities		51,187			22,135			36,912		—			110,234
Total liabilities		1,290,288			169,292			1,400,191		(226,953	)		2,632,818
Redeemable noncontrolling interest		10,444				—		—		—			10,444
Stockholders' equity		2,237,507			2,684,983			1,870,250		(4,555,233	)		2,237,507
Total liabilities and stockholders' equity	$	3,538,239		$	2,854,275		$	3,270,441	$	(4,782,186	)	$	4,880,769

Schedule Of Condensed Consolidating Statements Of Cash Flows


Condensed Consolidating Statements of Cash Flows
Nine Months Ended September 30, 2011
(unaudited)

					Guarantor			Non-Guarantor
		Parent/Issuer			Subsidiaries			Subsidiaries			Eliminations			Consolidated
								(In thousands)
Cash provided by (used in) operating
activities	$	(444,664	)	$	613,179		$	302,852		$	-		$	471,367
Investing Activities
Acquisition of ICG, net of cash acquired		(2,894,339	)		-			-			-			(2,894,339	)
Increase in restricted cash		(5,939	)		-			-			-			(5,939	)
Capital expenditures		(5,137	)		(135,640	)		(75,122	)		-			(215,899	)
Proceeds from dispositions of property, plant
and equipment		–			25,010			123			-			25,133
Purchases of investments and advances to
affiliates		(777,341	)		(29,872	)		–			750,386			(56,827	)
Additions to prepaid royalties		–			(22,163	)		(3,972	)		–			(26,135	)
Cash used in investing activities		(3,682,756	)		(162,665	)		(78,971	)		750,386			(3,174,006	)

Financing Activities

Proceeds from the issuance of senior notes		2,000,000			–			-			-			2,000,000
Proceeds from the issuance of common stock,
net		1,267,776			–			-			-			1,267,776
Contributions from parent		-			750,386			-			(750,386	)		–
Payments to retire debt		-			(604,096	)		-			-			(604,096	)
Net increase (decrease) in borrowings under
lines of credit and commercial paper program		340,000			–			(56,904	)		-			283,096
Net payments on other debt		(8,792	)		–			–			-			(8,792	)
Debt financing costs		(114,563	)		–			(24	)		-			(114,587	)
Dividends paid		(57,470	)		–			–			-			(57,470	)
Issuance of common stock under incentive
plans		1,628			–			–			-			1,628
Transactions with affiliates, net		742,906			(596,588	)		(146,318	)		-			–
Cash provided by (used in) financing
activities		4,171,485			(450,298	)		(203,246	)		(750,386	)		2,767,555
Increase in cash and cash equivalents		44,065			216			20,635			-			64,916
Cash and cash equivalents, beginning of
period		13,713			64			79,816			-			93,593
Cash and cash equivalents, end of period	$	57,778		$	280		$	100,451		$	-		$	158,509


Condensed Consolidating Statements of Cash Flows
Nine Months Ended September 30, 2010
					(unaudited)

					Guarantor			Non-Guarantor
		Parent/Issuer			Subsidiaries			Subsidiaries			Consolidated
					(In thousands)
Cash provided by (used in) operating
activities	$	(224,066	)	$	404,836		$	275,910		$	456,680
Investing Activities
Capital expenditures		(3,942	)		(141,825	)		(75,816	)		(221,583	)
Proceeds from dispositions of property, plant and
equipment		–			178			74			252
Purchases of investments and advances to affiliates		(12,671	)		(4,069	)		–			(16,740	)
Additions to prepaid royalties		–			(20,880	)		(2,835	)		(23,715	)
Cash used in investing activities		(16,613	)		(166,596	)		(78,577	)		(261,786	)

Financing Activities
Proceeds from the issuance of senior notes		500,000			–			–			500,000
Payments to retire debt		–			–			(505,627	)		(505,627	)
Net increase (decrease) in borrowings under lines of
credit and commercial paper program		(120,000	)		–			1,663			(118,337	)
Net payments on other debt		(9,794	)		–			–			(9,794	)
Debt financing costs		(11,901	)		–			(729	)		(12,630	)
Dividends paid		(47,121	)		–			–			(47,121	)
Issuance of common stock under incentive plans		339			–			–			339
Contribution from noncontrolling interest		–			–			891			891
Transactions with affiliates, net		(123,309	)		(238,252	)		361,561			–
Cash provided by (used in) financing
activities		188,214			(238,252	)		(142,241	)		(192,279	)
Increase (decrease) in cash and cash equivalents		(52,465	)		(12	)		55,092			2,615
Cash and cash equivalents, beginning of
period		54,255			64			6,819			61,138
Cash and cash equivalents, end of period	$	1,790		$	52		$	61,911		$	63,753

Basis Of Presentation (Details)	9 Months Ended
Basis Of Presentation (Details)	Sep. 30, 2011
Basis Of Presentation [Abstract]
Company's membership interest percentage in joint venture	99.00%
Number of mining complexes operated	23

Business Combination (Narrative) (Details) - USD ($) $ in Thousands, shares in Millions				3 Months Ended		9 Months Ended
	Jul. 08, 2011	Jun. 16, 2011	Jun. 08, 2011	Sep. 30, 2011	Jun. 30, 2011	Sep. 30, 2011	Sep. 30, 2010	Jun. 14, 2011
Purchase of common stock value								$ 3,100,000
Proceeds from the issuance of common stock, net			$ 1,250,000			$ 1,267,776
Number of shares sold	0.7		48.0
Proceeds from issuance of $2 billion in aggregate principal amount of senior notes						2,000,000	$ 500,000
Subsequent adjustment to previously reported cost of sales					$ 5,600
Revenues related to the acquired operations included in the statement of income since acquisition				$ 295,600		343,600
Income before income taxes related to the acquired operations included in the statement of income since acquisition				34,900		43,600
Restricted cash				$ 21,400		$ 21,400
Number Of Mining Complexes - Appalachia [Member]
Number of mining complexes operated		12
Number of mining complexes being developed		one
Number Of Mining Complexes - Illinois [Member]
Number of mining complexes operated		one

Business Combination (Summary Of Acquisition Related Activities) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2011 USD ($)
Consideration paid, net of cash acquired	$ 2,894,339
Restricted cash	15,500
Receivables	114,200
Inventories	87,000
Net property, plant and equipment, including mineral rights	4,510,600
Goodwill	425,000
Other assets	49,200
Accounts Payable	(82,600)
Other accrued expenses and current liabilities	(61,500)
Debt	(604,800)
Litigation accrual	(106,000)
Accrued postretirement benefits	(47,700)
Asset retirement obligation	(80,400)
Deferred income taxes, net	(1,189,900)
Other noncurrent liabilities	(35,400)
Net tangible and intangible assets acquired	2,894,400
Coal Supply Agreement [Member]
Coal supply agreements, net	$ (98,800)

Business Combination (Summary of Adjustments to the Purchase Price and Provisional Fair Values) $ in Millions	3 Months Ended
	Sep. 30, 2011 USD ($)
Business Combination [Abstract]
Inventories	$ 9.5
Net property, plant and equipment, including mineral rights	(5.8)
Coal supply agreements, net	(21.2)
Other	1.5
Purchase price adjustment-cash received	$ (16.0)

Business Combination (Summary Of Unaudited Pro Forma) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Business Combination [Abstract]
Total revenues as reported	$ 1,198,673	$ 874,705	$ 3,057,139	$ 2,350,874
Total revenues pro forma	1,198,700	1,176,900	3,596,800	3,212,600
Income before income taxes as reported	13,704	54,800	88,053	124,252
Income (loss) before income taxes pro forma	$ 22,300	$ 47,500	$ 72,600	$ (66,900)

Business Combination (Schedule Of Costs And Expenses Reflected In The Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011
Severance costs	$ 2,977	$ 16,475
Write off of acquired assets		7,316
Bridge financing fees		49,490
Total cost and expenses	4,694	126,353
ICG [Member]
Costs of completing the acquisition		23,503
Parent/Issuer [Member]
Costs of completing the acquisition	$ 1,717	29,569
Bridge financing fees		$ 49,490

- Definition

The charge against earnings in the period, comprised of costs associated with restructuring activities not otherwise specified in the taxonomy pursuant to a duly authorized plan, excluding a discontinued operation as defined by generally accepted accounting principles. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, but excludes costs associated with the retirement of a long-lived asset and severance costs associated with established compensation plans.

+ References + Details

- Definition

The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
-Subsection 3, 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS146-1
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5-8
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 112
-Paragraph 7
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 146
-Paragraph 8-13, 20
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.P.3)
-URI http://asc.fasb.org/extlink&oid=6394695&loc=d3e140864-122747

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=6394695&loc=d3e140904-122747

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(10)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

+ Details

Equity Offering (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions			9 Months Ended
	Jul. 08, 2011	Jun. 08, 2011	Sep. 30, 2011
Equity Offering [Abstract]
Number of shares sold	0.7	48.0
Common stock, public offering price		$ 27.00
Proceeds from the sale of common stock		$ 1,250,000	$ 1,267,776
Proceeds from shares issued for underwriters' over-allotments	$ 18,400

Debt (Narrative) (Details) - USD ($)		2 Months Ended	3 Months Ended		9 Months Ended
Debt (Narrative) (Details) - USD ($)	Jul. 14, 2011	Aug. 15, 2011	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Jun. 30, 2011	Jun. 14, 2011
Restricted cash			$ 21,428,000		$ 21,428,000
Debt assumed in acquisition			604,800,000		604,800,000
Net loss resulting from early retirement of debt			1,708,000	$ 6,776,000	$ 1,958,000	$ 6,776,000
Line of credit facility maturity term					5
Line of credit facility, expiration date					June 14, 2016
Line of credit facility, unused capacity, commitment fee percentage					0.50%
Secured revolving credit facility maximum borrowing amount			2,000,000,000		$ 2,000,000,000
Line of credit facility, remaining borrowing capacity			1,000,000,000		1,000,000,000
Letters of credit outstanding, amount			141,000,000		$ 141,000,000
7.00% Senior Notes Due June 15, 2019 [Member]
Registration statement effective date deadline							June 13, 2012
Registration Rights agreement violation per annum penalty in first 90 days					0.25%
Registration rights agreement violation additional per annum penalty					0.25%
Registration Rights agreement violation maximum per annum penalty					1.00%
7.25% Senior Notes Due 2021 [Member]
Registration statement effective date deadline							June 13, 2012
Registration Rights agreement violation per annum penalty in first 90 days					0.25%
Registration rights agreement violation additional per annum penalty					0.25%
Registration Rights agreement violation maximum per annum penalty					1.00%
Prior To June 15, 2014 [Member]
Percentage of maximum redemption aggregate principal amount from equity proceeds					35.00%
Revolving Credit Facility [Member]
Incurred financing fees			20,700,000		$ 20,700,000
Line of credit borrowings outstanding			300,000,000		300,000,000
Accounts Securitization Program [Member]
Line of credit borrowings outstanding			40,000,000		$ 40,000,000
9.125% Senior Notes Due April 1, 2018 [Member]
Restricted cash								$ 260,700,000
Accrued interest	$ 5,200,000
4.00% Convertible Senior Notes Due April 1, 2017 [Member]
Calculated conversion rate		$ 2,614.6848
Principal amount increment for conversion		1,000
Debt Instrument, Convertible, Latest Date					August 17, 2011
Debt assumed in acquisition								298,500,000
9.00% Convertible Senior Notes Due August 1, 2012 [Member]
Calculated conversion rate		2,392.73414
Principal amount increment for conversion		$ 1,000
Debt Instrument, Convertible, Latest Date					August 17, 2011
Debt assumed in acquisition								$ 1,700,000
Senior Notes [Member]
Tender offer price upon change in control					101.00%
Incurred financing fees			44,200,000		$ 44,200,000
ICG Debt [Member]
Debt assumed in acquisition			54,000,000		54,000,000
Net loss resulting from early retirement of debt			$ (1,700,000)		$ (2,000,000)
June 15, 2015 through June 14, 2016 [Member] \| 7.00% Senior Notes Due June 15, 2019 [Member]
Call premium					103.50%
June 15, 2016 through June 14, 2017 [Member] \| 7.00% Senior Notes Due June 15, 2019 [Member]
Call premium					101.75%
June 15, 2016 through June 14, 2017 [Member] \| 7.25% Senior Notes Due 2021 [Member]
Call premium					103.625%
June 15, 2017 and beyond [Member] \| 7.00% Senior Notes Due June 15, 2019 [Member]
Call premium					100.00%
June 15, 2017 and beyond [Member] \| 7.25% Senior Notes Due 2021 [Member]
Call premium					100.00%
June 15, 2017 through June 14, 2018 [Member] \| 7.25% Senior Notes Due 2021 [Member]
Call premium					102.417%
June 15, 2018 through June 14, 2019 [Member] \| 7.25% Senior Notes Due 2021 [Member]
Call premium					101.208%
Repayment of Debt [Member] \| 9.125% Senior Notes Due April 1, 2018 [Member]
Subsequent event, senior notes redeemed	$ 251,400,000

Debt (Debt) (Details) - USD ($)	9 Months Ended
Debt (Debt) (Details) - USD ($)	Sep. 30, 2011	Dec. 31, 2010
Commercial paper		$ 56,904,000
Indebtedness to banks under credit facilities	$ 340,000,000
Other	8,858,000	14,093,000
Total	3,888,486,000	1,609,741,000
Less current maturities of debt and short-term borrowings	47,156,000	70,997,000
Long-term debt	3,841,330,000	1,538,744,000
7.00% Senior Notes Due June 15, 2019 [Member]
Senior notes	$ 1,000,000,000
Senior notes interest rate	7.00%
Due date of senior notes	Jun. 15, 2019
7.25% Senior Notes Due June 15, 2021 [Member]
Senior notes	$ 1,000,000,000
Senior notes interest rate	7.25%
Due date of senior notes	Jun. 15, 2021
6.75% Senior Notes Due July 1, 2013 [Member]
Senior notes	$ 451,132,000	451,618,000
Face value of senior notes	$ 450,000,000
Senior notes interest rate	6.75%
Due date of senior notes	Jul. 01, 2013
8.75% Senior Notes Due August 1, 2016 [Member]
Senior notes	$ 588,496,000	587,126,000
Face value of senior notes	$ 600,000,000
Senior notes interest rate	8.75%
Due date of senior notes	Aug. 01, 2016
7.25% Senior Notes Due October 1, 2020 [Member]
Senior notes	$ 500,000,000	$ 500,000,000
Senior notes interest rate	7.25%

Acquired Sales Contracts (Narrative) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2011 USD ($)
Coal supply agreement asset, purchase price allocation	$ 30.8
Coal supply agreement liability, purchase price allocation	129.7
Amortization expense (income) of acquired sales contracts year one	29.0
Amortization expense (income) of acquired sales contracts year two	20.0
Amortization expense (income) of acquired sales contracts year three	7.0
Amortization expense (income) of acquired sales contracts year four	8.0
Amortization expense (income) of acquired sales contracts year five	13.0
Amortization expense (income) of acquired sales contracts after year five	8.0
Current Asset [Member]
Business acquisition current assets	13.7
Current Liabilities [Member]
Business acquisition current liabilities	$ 52.3

Acquired Sales Contracts (Schedule Of Acquired Sales Contracts) (Details) - USD ($) $ in Millions	Sep. 30, 2011	Dec. 31, 2010
Net total, assets		$ 6,036.0
Net total, liabilities	$ 88,096.0
Acquired fair value	145,213.0	114,453.0
Accumulated Amortization, Asset	(105,845.0)	(82,376.0)
Total	39,368.0	32,077.0
Acquired fair value	170,341.0	40,654.0
Liability, Accumulated Amortization	(42,877.0)	(14,613.0)
Total	127,464.0	26,041.0
Current Asset [Member]
Coal supply agreement asset	23,474.0	25,063.0
Other Assets [Member]
Coal supply agreement asset	15,894.0	7,014.0
Accrued Expenses And Other Current Liabilities [Member]
Coal Supply Agreement Obligation Liability	58,049.0	5,615.0
Other Noncurrent Liabilities [Member]
Coal Supply Agreement Obligation Liability	$ 69,415.0	$ 20,426.0

Investments (Narrative) (Details) - USD ($) $ in Thousands	9 Months Ended
Investments (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2011	Jul. 31, 2011	Jan. 31, 2011	Dec. 31, 2010
Future development costs, maximum limit	$ 70,900
Equity investments	224,684			$ 177,451
Millennium [Member]
Ownership interest			38.00%
Equity investments	25,339		$ 25,000
Tongue River [Member]
Ownership interest		33.00%
Equity investments	$ 12,989

Investments (Schedule Of Equity Method Investments) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2011 USD ($)
Balance at December 31, 2010	$ 177,451
Investments in affiliates	43,489
Advances to (distributions from) affiliates, net	(5,156)
Equity in comprehensive income (loss)	8,900
Balance at September 30, 2011	224,684
Balance at December 31, 2010	23,900
Balance at September 30, 2011	33,194
Knight Hawk [Member]
Balance at December 31, 2010	131,250
Advances to (distributions from) affiliates, net	(11,450)
Equity in comprehensive income (loss)	15,807
Balance at September 30, 2011	135,607
Balance at December 31, 2010	1,700
DKRW [Member]
Balance at December 31, 2010	21,961
Equity in comprehensive income (loss)	(1,631)
Balance at September 30, 2011	20,330
Balance at December 31, 2010	18,100
Balance at September 30, 2011	28,417
DTA [Member]
Balance at December 31, 2010	14,472
Advances to (distributions from) affiliates, net	4,394
Equity in comprehensive income (loss)	(3,713)
Balance at September 30, 2011	15,153
Tenaska [Member]
Balance at December 31, 2010	9,768
Investments in affiliates	5,500
Equity in comprehensive income (loss)	(2)
Balance at September 30, 2011	15,266
Balance at December 31, 2010	4,100
Balance at September 30, 2011	4,777
Millennium [Member]
Investments in affiliates	25,000
Advances to (distributions from) affiliates, net	1,900
Equity in comprehensive income (loss)	(1,561)
Balance at September 30, 2011	25,339
Tongue River [Member]
Investments in affiliates	12,989
Balance at September 30, 2011	$ 12,989

Derivatives (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended
Derivatives (Narrative) (Details) $ in Millions	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Dec. 31, 2010 USD ($)
Net unrealized and realized gains (losses) related to trading portfolio	$ (2.2)	$ (0.8)	$ 1.7	$ (2.9)
Gain on derivative contracts designated as hedge instruments in cash flow hedges to be reclassified from OCI into earnings during the next twelve months	$ 9.3		$ 9.3
Minimum Purchase [Member]
Gallons of diesel fuel purchased annually			90,000,000
Maximum Purchase [Member]
Gallons of diesel fuel purchased annually			100,000,000
Year One [Member]
Percent of diesel purchases hedged	70.00%		70.00%
Value of trading portfolio realized			$ 2.4
Year Two [Member]
Percent of diesel purchases hedged	55.00%		55.00%
Value of trading portfolio realized			$ (0.9)
Year Three [Member]
Value of trading portfolio realized			$ (1.0)
Heating oil-fuel surchages [Member]
Quantities under derivative contracts	19,100,000		19,100,000
Current Assets [Member]
Current asset for the right to reclaim cash collateral	$ 10.7		$ 10.7		$ 10.3
Heating Oil [Member] \| Heating Oil-diesel purchases [Member]
Quantities under derivative contracts	68,000,000		68,000,000
One Year from Balance Sheet Date [Member] \| Coal [Member]
Quantities under derivative contracts	500,000		500,000
One Year from Balance Sheet Date [Member] \| Coal [Member] \| Coal Purchases [Member]
Quantities under derivative contracts	500,000		500,000
More than One and within Two Years from Balance Sheet Date [Member] \| Coal [Member]
Quantities under derivative contracts	1,700,000		1,700,000
More than One and within Two Years from Balance Sheet Date [Member] \| Coal [Member] \| Coal Purchases [Member]
Quantities under derivative contracts	200,000		200,000
More than Two and within Three Years from Balance Sheet Date [Member] \| Coal [Member]
Quantities under derivative contracts	700,000		700,000
More than Three and within Four Years from Balance Sheet Date [Member] \| Coal [Member]
Quantities under derivative contracts	1,400,000		1,400,000
More than Four and within Five Years from Balance Sheet Date [Member] \| Coal [Member]
Quantities under derivative contracts	700,000		700,000

Derivatives (Disclosure Of Fair Value Of Derivatives) (Details) - USD ($) $ in Thousands	Sep. 30, 2011	Dec. 31, 2010
Derivative Assets	$ 26,936	$ 51,068
Derivative Liabilities	(18,611)	(27,349)
Effect of counterparty netting in derivative assets	(12,787)	(22,402)
Effect of counterparty netting in derivative liabilities	12,787	22,402
Net derivative assets as classified in the balance sheet	14,149	28,666
Net derivative liabilities as classified in the balance sheet	(5,824)	(4,947)
Net derivatives as classified in the balance sheet	8,325	23,719
Designated as Hedging Instrument [Member]
Derivative Assets	12,060	15,484
Derivative Liabilities	(1,270)	(2,350)
Designated as Hedging Instrument [Member] \| Coal [Member]
Derivative Assets	2,708	2,009
Derivative Liabilities	(1,270)	(2,350)
Designated as Hedging Instrument [Member] \| Heating Oil-diesel purchases [Member]
Derivative Assets	9,352	13,475
Derivative Liabilities
Not Designated as Hedging Instrument [Member]
Derivative Assets	14,876	35,584
Derivative Liabilities	(17,341)	(24,999)
Not Designated as Hedging Instrument [Member] \| Coal Held for Trading Purposes [Member]
Derivative Assets	10,862	34,445
Derivative Liabilities	(10,365)	(24,087)
Not Designated as Hedging Instrument [Member] \| Coal [Member]
Derivative Assets	1,812	1,139
Derivative Liabilities	(6,976)	$ (912)
Not Designated as Hedging Instrument [Member] \| Heating oil-fuel surchages [Member]
Derivative Assets	$ 2,202

Derivatives (Net Derivatives As Reflected On The Balance Sheets) (Details) - USD ($) $ in Thousands	Sep. 30, 2011	Dec. 31, 2010
Derivative assets	$ 26,936	$ 51,068
Net derivatives as reflected on the balance sheet	8,325	23,719
Coal [Member]
Coal derivative assets	2,595	15,191
Coal derivative liabilities	(5,824)	(4,947)
Other Current Assets [Member] \| Heating Oil [Member]
Derivative assets	$ 11,554	$ 13,475

- Definition

Fair values as of the balance sheet date for all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Section A
-Paragraph 4
-Chapter 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FIN39-1
-Paragraph 10A, 10B
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 4, 17
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13495-108611

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Current Assets
-URI http://asc.fasb.org/extlink&oid=6509628

+ Details

- Definition

Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 7
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FIN39-1
-Paragraph 10A, 10B
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 4, 17
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Current Liabilities
-URI http://asc.fasb.org/extlink&oid=6509677

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13495-108611

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

+ Details

Derivatives (Effects Of Derivatives On Measures Of Financial Performance) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Gain (Loss) Recognized in OCI (Effective Portion)	$ (5,840)	$ 2,017	$ 4,052	$ (6,112)
Gains (Losses) Reclassified from OCI into Income (Effective Portion)	5,588	(999)	15,736	(2,969)
Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)
Coal Purchases [Member]
Gain (Loss) Recognized in OCI (Effective Portion)	(1,274)	(2,535)	(2,053)	5,534
Gains (Losses) Reclassified from OCI into Income (Effective Portion)		(866)		(1,202)
Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)
Coal Sales [Member]
Gain (Loss) Recognized in OCI (Effective Portion)	1,820	1,500	4,570	(6,138)
Gains (Losses) Reclassified from OCI into Income (Effective Portion)	466	(226)	790	(1,556)
Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)
Coal [Member] \| Change In Fair Value Of Coal Derivatives And Coal Trading Activities Net [Member]
Derivatives Not Designated as Hedging Instruments, Losses, Unrealized	(6,131)	(993)	(7,550)	(9,381)
Coal [Member] \| Other Operating Income, Net [Member]
Derivatives Not Designated as Hedging Instruments, Gain, Realized	166	1,079	313	3,931
Heating Oil-diesel purchases [Member]
Gain (Loss) Recognized in OCI (Effective Portion)	(6,386)	3,052	1,535	(5,508)
Gains (Losses) Reclassified from OCI into Income (Effective Portion)	5,122	$ 93	14,946	(211)
Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing)
Heating oil-fuel surchages [Member] \| Other Operating Income, Net [Member]
Derivatives Not Designated as Hedging Instruments, Losses, Unrealized	$ (2,501)		$ (2,501)

Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2011	Dec. 31, 2010
Inventories [Abstract]
Coal	$ 180,988	$ 115,647
Repair parts and supplies, net of allowance	165,343	119,969
Inventories	346,331	235,616
Repair parts and supplies stated net of an allowance for slow-moving and obsolete inventories	$ 13,400	$ 12,700

- Definition

The amount of the valuation account as of the balance sheet date which reduces the carrying amount of inventory to net realizable value; takes into consideration such factors as market value, excessive quantities based on expected sales, technological obsolescence, and shrinkage. May also provide for estimated product returns or price concessions pertaining to product cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 6
-Subparagraph a
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 9
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 4
-Paragraph 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 4
-Paragraph 8, 9, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6386567&loc=d3e3927-108312

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.BB)
-URI http://asc.fasb.org/extlink&oid=6386940&loc=d3e100047-122729

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690

+ Details

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011	Dec. 31, 2010
Fair value of senior notes and other long-term debt, including amounts classified as current	$ 3,900.0	$ 3,900.0	$ 1,700.0
Level 3 [Member]
Net unrealized losses related to level 3 financial instruments	$ 11.7	$ 14.7

Fair Value Measurements (Summary Of Financial Assets And Liabilities Accounted For At Fair Value) (Details) - USD ($) $ in Thousands	Sep. 30, 2011	Dec. 31, 2010
Assets:
Investments in equity securities	$ 5,351
Derivatives	14,149	$ 28,666
Total assets	19,500
Liabilities:
Derivatives	5,824	$ 4,947
Level 1 [Member]
Assets:
Investments in equity securities	5,351
Derivatives	1,018
Total assets	6,369
Liabilities:
Derivatives
Level 2 [Member]
Assets:
Investments in equity securities
Derivatives	2,695
Total assets	2,695
Liabilities:
Derivatives	(415)
Level 3 [Member]
Assets:
Derivatives	10,436
Total assets	10,436
Liabilities:
Derivatives	$ 6,239

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References + Details

- Definition

Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

+ References + Details

- Definition

Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements.

+ References + Details

Fair Value Measurements (Summary Of Change In The Fair Values Of Financial Instruments Categorized As Level 3) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011
Fair Value Measurements [Abstract]
Balance, beginning of period	$ 10,474	$ 9,183
Realized and unrealized losses recognized in earnings, net	(8,016)	(15,140)
Realized and unrealized gains (losses) recognized in other comprehensive income, net	(6,702)	(3,227)
Purchases	9,935	20,407
Issuances		(2,160)
Settlements	(1,494)	(4,866)
Balance, end of period	$ 4,197	$ 4,197

Stock-Based Compensation And Other Incentive Plans (Details) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011 USD ($) $ / shares	Sep. 30, 2010 USD ($)	Sep. 30, 2011 USD ($) $ / shares shares	Sep. 30, 2010 USD ($)	Dec. 31, 2010 USD ($)
Options issued during period \| shares			700,000
Weighted average exercise price of options granted	$ 32.18		$ 32.18
Common stock issuable under option granted, weighted average grant date fair value			$ 14.18
Option, weighted average risk free rate			1.92%
Option, weighted average dividend yield			1.25%
Option, weighted average volatility			57.43%
Compensation expense recognition period			3
Amounts unpaid for all grants \| $	$ 10.0		$ 10.0		$ 6.4
Allocated stock-based compensation expense \| $	$ 3.4	$ 3.4	$ 12.6	$ 12.3
Stock Option [Member]
Vesting period of option (Years)			4.5
Share based awards vesting period			three
Restricted Stock [Member]
Shares granted during the period \| shares			130,950
Weighted average grant-date fair value			$ 31.30
Share based awards vesting period			three

Workers' Compensation Expense (Worker's Compensation Expense) (Details) - Workers' Compensation [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Service cost	$ 807	$ 182	$ 1,246	$ 545
Interest cost	619	169	1,177	507
Net amortization	(109)	(465)	(370)	(1,395)
Net benefit cost (credit)	1,317	(114)	2,053	(343)
Traumatic injury claims and assessments	5,207	2,642	10,856	6,562
Total workers' compensation expense	$ 6,524	$ 2,528	$ 12,909	$ 6,219

- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References + Details

- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 106
-Paragraph 518
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph a, h
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Service Cost (Component of Net Periodic Pension Cost)
-URI http://asc.fasb.org/extlink&oid=6525008

+ Details

Employee Benefit Plans (Pension And Other Postretirement Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Pension Plans, Defined Benefit [Member]
Service cost	$ 4,122	$ 3,967	$ 12,367	$ 11,902
Interest cost	4,063	3,955	12,190	11,866
Expected return on plan assets	(5,453)	(4,848)	(16,359)	(14,544)
Amortization of prior service cost (credit)	(47)	44	(142)	130
Amortization of other actuarial (gains) losses	2,187	1,782	6,561	5,348
Net benefit cost (credit)	4,872	4,900	14,617	14,702
Other Postretirement Benefit Plans, Defined Benefit [Member]
Service cost	1,493	378	2,416	1,132
Interest cost	1,125	520	2,152	1,562
Amortization of prior service cost (credit)	(636)	(591)	(1,773)	(1,773)
Amortization of other actuarial (gains) losses	(775)	(729)	(2,325)	(2,188)
Net benefit cost (credit)	$ 1,207	$ (422)	$ 470	$ (1,267)

- Definition

An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

+ Details

- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References + Details

- Definition

+ References

+ Details

Comprehensive Income (Components Of Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Comprehensive Income [Abstract]
Net income attributable to Arch Coal, Inc.	$ 19,056	$ 46,678	$ 82,128	$ 111,038
Pension, postretirement and other post-employment benefits, reclassifications into net income	388	28	1,254	84
Unrealized gains (losses) on available-for-sale securities	(569)	738	(1,256)	(178)
Unrealized gains (losses) on derivatives	(3,671)	1,200	2,703	(3,889)
Reclassifications of (gains) losses into net income	(3,575)	639	(10,059)	1,856
Total comprehensive income	$ 11,629	$ 49,283	$ 74,770	$ 108,911

- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References + Details

- 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/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 87-21
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph a
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 10, 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28, 29, 30
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 19

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 20
-Article 9

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=6518256

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6519514

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.18)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.19)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e565-108580

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.22)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A7
-Appendix A

+ Details

- Definition

Gross appreciation or the gross loss in value of the total unsold securities. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 24
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 14, 17, 19, 22, 26
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 2
-Subparagraph (e)-(g)
-URI http://asc.fasb.org/extlink&oid=6920433&loc=d3e998-108581

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Net of tax effect of the reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 24
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Number 133
-Paragraph 31, 46
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Paragraph 11
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Reclassification Adjustments
-URI http://asc.fasb.org/extlink&oid=6522872

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-Name Accounting Standards Codification
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-Number 51
-Paragraph 38
-Subparagraph c(3)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 46
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Number 130
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+ Details

Earnings Per Common Share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Earnings Per Common Share
Basic weighted average shares outstanding	211,337	162,391	182,898	162,384
Effect of common stock equivalents under incentive plans	637	783	952	744
Diluted weighted average shares outstanding	211,974	163,174	183,850	163,128
Effect of options to purchase common stock	3,000	3,400	2,100	2,700

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14
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-Number 128
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

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-Name Emerging Issues Task Force (EITF)
-Number 07-4
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+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References + Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
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-URI http://asc.fasb.org/extlink&oid=6528421

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+ Details

Guarantees (Details) Unit12 in Millions, $ in Millions	9 Months Ended
Guarantees (Details) Unit12 in Millions, $ in Millions	Sep. 30, 2011 USD ($)
Magnum [Member]
Guarantee obligations, maximum exposure, undiscounted	$ 19.5
Excess of the current market cost of purchasing coal over the selling price	$ 264.3
Volume of purchased coal in tons	10.3
Performance Guarantee [Member] \| Magnum [Member]
Volume of purchased coal in tons	0.9
Bonding Requirements [Member] \| Magnum [Member]
Surety bonds posted in the company's favor	$ 48.9
Letters of credit posted in the Company's favor	32.7
Guarantee obligations, maximum exposure, undiscounted	38.5
Indemnification Agreement [Member]
Guarantee obligations, maximum exposure, undiscounted	$ 22.3

Contingencies (Details) $ in Millions	9 Months Ended
Contingencies (Details) $ in Millions	Sep. 30, 2011 USD ($)
Purchase replacement coal	$ 100.0
Damages and interest awarded	104.1
Appeal Bond	124.9
Amount accrued	106.7
Interest recognized post-acquisition	1.8
Maximum [Member]
Aggregate amount of past and future damages	377.0
Minimum [Member]
Aggregate amount of past and future damages	$ 228.0

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
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-Paragraph 1
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+ Details

Segment Information (Schedule Of Operating Segment Results) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Revenues	$ 1,198,673	$ 874,705	$ 3,057,139	$ 2,350,874
Income from operations	92,266	98,347	291,683	237,046
Total assets	9,855,261	4,834,786	9,855,261	4,834,786	$ 4,880,769
Depreciation, depletion and amortization	123,026	92,857	301,746	269,135
Amortization of acquired sales contacts, net	(12,186)	10,038	(4,753)	26,005
Capital expenditures	108,174	49,625	$ 215,899	221,583
Number of reportable business segments			three
PRB [Member]
Revenues	394,012	440,439	$ 1,178,537	1,170,353
Income from operations	38,630	51,787	121,119	101,525
Total assets	2,240,458	2,304,277	2,240,458	2,304,277
Depreciation, depletion and amortization	42,676	49,005	125,532	138,059
Amortization of acquired sales contacts, net	3,802	10,038	15,349	26,005
Capital expenditures	20,937	8,164	39,422	12,614
WBIT [Member]
Revenues	168,795	138,039	513,388	402,902
Income from operations	24,653	14,816	95,218	41,122
Total assets	667,658	677,968	667,658	677,968
Depreciation, depletion and amortization	19,125	18,940	61,753	57,700
Capital expenditures	16,111	20,703	38,003	54,507
APP [Member]
Revenues	611,403	296,227	1,336,581	777,619
Income from operations	77,511	55,664	224,561	147,336
Total assets	5,159,710	701,670	5,159,710	701,670
Depreciation, depletion and amortization	59,576	24,435	108,904	72,190
Amortization of acquired sales contacts, net	(16,022)		(20,145)
Capital expenditures	62,121	16,910	108,711	41,519
Other [Member]
Revenues	24,463		28,633
Income from operations	(1,713)		(1,814)
Total assets	222,014		222,014
Depreciation, depletion and amortization	3,781		4,386
Amortization of acquired sales contacts, net	34		43
Capital expenditures	4,705		9,078
Corporate, Other and Eliminations [Member]
Income from operations	(46,815)	(23,920)	(147,401)	(52,937)
Total assets	1,565,421	1,150,871	1,565,421	1,150,871
Depreciation, depletion and amortization	(2,132)	477	1,171	1,186
Capital expenditures	$ 4,300	$ 3,848	$ 20,685	$ 112,943

Segment Information (Reconciliation Statement Of Segment Income from Operations To Consolidated Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Segment Information [Abstract]
Income from operations	$ 92,266	$ 98,347	$ 291,683	$ 237,046
Interest expense	(77,694)	(37,698)	(154,523)	(107,906)
Interest income	840	927	2,341	1,888
Bridge financing costs related to ICG			(49,490)
Net loss resulting from early retirement of debt	(1,708)	(6,776)	(1,958)	(6,776)
Income before income taxes	$ 13,704	$ 54,800	$ 88,053	$ 124,252

Supplemental Condensed Consolidating Financial Information (Schedule Of Condensed Consolidating Statements Of Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Revenues	$ 1,198,673	$ 874,705	$ 3,057,139	$ 2,350,874
Costs, expenses and other
Cost of sales	952,850	651,853	2,322,124	1,773,464
Depreciation, depletion and amortization	123,026	92,857	301,746	269,135
Amortization of acquired sales contracts, net	(12,186)	10,038	(4,753)	26,005
Selling, general and administrative expenses	33,276	26,999	92,750	89,509
Change in fair value of coal derivatives and coal trading activities, net	8,360	1,832	9,248	12,296
Acquisition and transition costs related to ICG	4,694		53,360
Gain on Knight Hawk transaction				(41,577)
Other operating (income) expense, net	(3,613)	(7,221)	(9,019)	(15,004)
Total operating expenses	1,106,407	776,358	2,765,456	2,113,828
Income from operations	92,266	98,347	291,683	237,046
Interest expense	(77,694)	(37,698)	(154,523)	(107,906)
Interest income	840	927	2,341	1,888
Interest expense, net	(76,854)	(36,771)	(152,182)	(106,018)
Bridge financing costs related to ICG			(49,490)
Net loss resulting from early retirement of debt	(1,708)	(6,776)	(1,958)	(6,776)
Other non-operating expense, Total	(1,708)	(6,776)	(51,448)	(6,776)
Income before income taxes	13,704	54,800	88,053	124,252
Provision for (benefit from) income taxes	(5,583)	7,941	5,103	12,889
Net income	19,287	46,859	82,950	111,363
Less: Net income attributable to noncontrolling interest	(231)	(181)	(822)	(325)
Net income attributable to Arch Coal, Inc.	19,056	46,678	82,128	111,038
Parent/Issuer [Member]
Costs, expenses and other
Cost of sales	7,442	3,578	15,661	8,554
Depreciation, depletion and amortization	718	794	2,050	2,270
Selling, general and administrative expenses	20,263	18,245	59,198	60,139
Acquisition and transition costs related to ICG	4,694		53,360
Other operating (income) expense, net	(6,063)	(3,346)	(15,461)	(8,124)
Total operating expenses	27,054	19,271	114,808	62,839
Income from investment in subsidiaries	121,210	108,974	413,406	282,794
Income from operations	94,156	89,703	298,598	219,955
Interest expense	(84,045)	(38,041)	(172,700)	(102,996)
Interest income	3,593	3,138	11,645	7,293
Interest expense, net	(80,452)	(34,903)	(161,055)	(95,703)
Bridge financing costs related to ICG			(49,490)
Other non-operating expense, Total			(49,490)
Income before income taxes	13,704	54,800	88,053	124,252
Provision for (benefit from) income taxes	(5,583)	7,941	5,103	12,889
Net income	19,287	46,859	82,950	111,363
Less: Net income attributable to noncontrolling interest	(231)	(181)	(822)	(325)
Net income attributable to Arch Coal, Inc.	19,056	46,678	82,128	111,038
Guarantor Subsidiaries [Member]
Revenues	651,326	324,507	1,409,755	846,351
Costs, expenses and other
Cost of sales	522,636	229,731	1,062,692	591,692
Depreciation, depletion and amortization	83,775	52,302	181,059	142,961
Amortization of acquired sales contracts, net	(15,989)		(20,102)
Selling, general and administrative expenses	5,058	1,858	10,112	5,500
Change in fair value of coal derivatives and coal trading activities, net	8,360	1,832	9,248	12,296
Gain on Knight Hawk transaction				(41,577)
Other operating (income) expense, net	(30,509)	(35,107)	(87,210)	(84,031)
Total operating expenses	573,331	250,616	1,155,799	626,841
Income from operations	77,995	73,891	253,956	219,510
Interest expense	(942)	(745)	(3,793)	(2,104)
Interest income	108	119	540	283
Interest expense, net	(834)	(626)	(3,253)	(1,821)
Net loss resulting from early retirement of debt	(1,708)		(1,958)
Other non-operating expense, Total	(1,708)		(1,958)
Income before income taxes	75,453	73,265	248,745	217,689
Net income	75,453	73,265	248,745	217,689
Net income attributable to Arch Coal, Inc.	75,453	73,265	248,745	217,689
Non-Guarantor Subsidiaries [Member]
Revenues	547,347	550,198	1,647,384	1,504,523
Costs, expenses and other
Cost of sales	448,680	445,814	1,319,711	1,239,893
Depreciation, depletion and amortization	38,533	39,761	118,637	123,904
Amortization of acquired sales contracts, net	3,803	10,038	15,349	26,005
Selling, general and administrative expenses	9,751	8,818	28,768	29,226
Other operating (income) expense, net	5,255	2,040	12,384	5,120
Total operating expenses	506,022	506,471	1,494,849	1,424,148
Income from operations	41,325	43,727	152,535	80,375
Interest expense	(10,657)	(16,738)	(32,599)	(53,241)
Interest income	15,089	15,496	44,725	44,747
Interest expense, net	4,432	(1,242)	12,126	(8,494)
Net loss resulting from early retirement of debt		(6,776)		(6,776)
Other non-operating expense, Total		(6,776)		(6,776)
Income before income taxes	45,757	35,709	164,661	65,105
Net income	45,757	35,709	164,661	65,105
Net income attributable to Arch Coal, Inc.	45,757	35,709	164,661	65,105
Eliminations [Member]
Costs, expenses and other
Cost of sales	(25,908)	(27,270)	(75,940)	(66,675)
Selling, general and administrative expenses	(1,796)	(1,922)	(5,328)	(5,356)
Other operating (income) expense, net	27,704	29,192	81,268	72,031
Income from investment in subsidiaries	(121,210)	(108,974)	(413,406)	(282,794)
Income from operations	(121,210)	(108,974)	(413,406)	(282,794)
Interest expense	17,950	17,826	54,569	50,435
Interest income	(17,950)	(17,826)	(54,569)	(50,435)
Income before income taxes	(121,210)	(108,974)	(413,406)	(282,794)
Net income	(121,210)	(108,974)	(413,406)	(282,794)
Net income attributable to Arch Coal, Inc.	$ (121,210)	$ (108,974)	$ (413,406)	$ (282,794)

Supplemental Condensed Consolidating Financial Information (Schedule Of Condensed Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2009
Assets
Cash and cash equivalents	$ 158,509	$ 93,593	$ 63,753	$ 61,138
Restricted cash	21,428
Receivables	426,300	252,320
Inventories	346,331	235,616
Other	155,015	153,385
Total current assets	1,107,583	734,914
Property, plant and equipment, net	7,703,280	3,308,892
Other	1,044,398	836,963
Total other assets	1,044,398	836,963
Total assets	9,855,261	4,880,769	4,834,786
Liabilities and Stockholders' Equity
Accounts payable	293,446	198,216
Accrued expenses and other current liabilities	385,531	258,133
Current maturities of debt and short-term borrowings	47,156	70,997
Total current liabilities	726,133	527,346
Long-term debt	3,841,330	1,538,744
Asset retirement obligations	415,877	334,257
Accrued pension benefits	16,235	49,154
Accrued postretirement benefits other than pension	88,820	37,793
Accrued workers' compensation	64,421	35,290
Deferred income taxes	880,487
Other noncurrent liabilities	277,490	110,234
Total liabilities	6,310,793	2,632,818
Redeemable noncontrolling interest	11,261	10,444
Stockholders' equity	3,533,207	2,237,507
Total liabilities and stockholders' equity	9,855,261	4,880,769
Parent/Issuer [Member]
Assets
Cash and cash equivalents	57,778	13,713	1,790	54,255
Restricted cash	21,428
Receivables	63,111	31,458
Other	35,413	29,575
Total current assets	177,730	74,746
Property, plant and equipment, net	13,685	9,817
Investment in subsidiaries	8,632,002	4,555,233
Intercompany receivables	(2,243,557)	(1,807,902)
Note receivable from Arch Western	225,000	225,000
Other	456,885	481,345
Total other assets	7,070,330	3,453,676
Total assets	7,261,745	3,538,239
Liabilities and Stockholders' Equity
Accounts payable	33,646	10,753
Accrued expenses and other current liabilities	108,442	75,746
Current maturities of debt and short-term borrowings	4,357	14,093
Total current liabilities	146,445	100,592
Long-term debt	3,388,496	1,087,126
Asset retirement obligations	548	873
Accrued pension benefits	7,057	20,843
Accrued postretirement benefits other than pension	15,276	14,284
Accrued workers' compensation	14,866	15,383
Deferred income taxes	(4,162)
Other noncurrent liabilities	148,751	51,187
Total liabilities	3,717,277	1,290,288
Redeemable noncontrolling interest	11,261	10,444
Stockholders' equity	3,533,207	2,237,507
Total liabilities and stockholders' equity	7,261,745	3,538,239
Guarantor Subsidiaries [Member]
Assets
Cash and cash equivalents	280	64	52	64
Receivables	130,884	12,740
Inventories	173,564	85,196
Other	102,729	102,375
Total current assets	407,457	200,375
Property, plant and equipment, net	6,234,786	1,800,578
Intercompany receivables	813,061	508,624
Other	574,038	344,698
Total other assets	1,387,099	853,322
Total assets	8,029,342	2,854,275
Liabilities and Stockholders' Equity
Accounts payable	151,826	65,793
Accrued expenses and other current liabilities	132,785	31,123
Current maturities of debt and short-term borrowings	2,799
Total current liabilities	287,410	96,916
Long-term debt	1,702
Asset retirement obligations	107,002	32,029
Accrued pension benefits	(489)	4,407
Accrued postretirement benefits other than pension	50,241
Accrued workers' compensation	42,850	13,805
Deferred income taxes	884,649
Other noncurrent liabilities	75,565	22,135
Total liabilities	1,448,930	169,292
Stockholders' equity	6,580,412	2,684,983
Total liabilities and stockholders' equity	8,029,342	2,854,275
Non-Guarantor Subsidiaries [Member]
Assets
Cash and cash equivalents	100,451	79,816	$ 61,911	$ 6,819
Receivables	233,855	210,075
Inventories	172,767	150,420
Other	16,873	21,435
Total current assets	523,946	461,746
Property, plant and equipment, net	1,454,809	1,498,497
Intercompany receivables	1,430,496	1,299,278
Other	13,475	10,920
Total other assets	1,443,971	1,310,198
Total assets	3,422,726	3,270,441
Liabilities and Stockholders' Equity
Accounts payable	107,974	121,670
Accrued expenses and other current liabilities	145,854	153,217
Current maturities of debt and short-term borrowings	40,000	56,904
Total current liabilities	293,828	331,791
Long-term debt	451,132	451,618
Note payable to Arch Coal	225,000	225,000
Asset retirement obligations	308,327	301,355
Accrued pension benefits	9,667	23,904
Accrued postretirement benefits other than pension	23,303	23,509
Accrued workers' compensation	6,705	6,102
Other noncurrent liabilities	53,174	36,912
Total liabilities	1,371,136	1,400,191
Stockholders' equity	2,051,590	1,870,250
Total liabilities and stockholders' equity	3,422,726	3,270,441
Eliminations [Member]
Assets
Receivables	(1,550)	(1,953)
Total current assets	(1,550)	(1,953)
Investment in subsidiaries	(8,632,002)	(4,555,233)
Note receivable from Arch Western	(225,000)	(225,000)
Total other assets	(8,857,002)	(4,780,233)
Total assets	(8,858,552)	(4,782,186)
Liabilities and Stockholders' Equity
Accrued expenses and other current liabilities	(1,550)	(1,953)
Total current liabilities	(1,550)	(1,953)
Note payable to Arch Coal	(225,000)	(225,000)
Total liabilities	(226,550)	(226,953)
Stockholders' equity	(8,632,002)	(4,555,233)
Total liabilities and stockholders' equity	$ (8,858,552)	$ (4,782,186)

Supplemental Condensed Consolidating Financial Information (Schedule Of Condensed Consolidating Statements Of Cash Flows) (Details) - USD ($) $ in Thousands		9 Months Ended
	Jun. 08, 2011	Sep. 30, 2011	Sep. 30, 2010
Cash provided by (used in) operating activities		$ 471,367	$ 456,680
Investing Activities
Acquisition of ICG, net of cash acquired		(2,894,339)
Increase in restricted cash		(5,939)
Capital expenditures		(215,899)	(221,583)
Proceeds from dispositions of property, plant and equipment		25,133	252
Purchases of investments and advances to affiliates		(56,827)	(16,740)
Additions to prepaid royalties		(26,135)	(23,715)
Cash used in investing activities		(3,174,006)	(261,786)
Financing Activities
Proceeds from the issuance of senior notes		2,000,000	500,000
Proceeds from the sale of common stock	$ 1,250,000	1,267,776
Payments to retire debt		(604,096)	(505,627)
Net increase (decrease) in borrowings under lines of credit and commercial paper program		283,096	(118,337)
Net (payments) and proceeds from other debt		(8,792)	(9,794)
Debt financing costs		(114,587)	(12,630)
Dividends paid		(57,470)	(47,121)
Issuance of common stock under incentive plans		1,628	339
Contribution from noncontrolling interest			891
Cash provided by (used in) financing activities		2,767,555	(192,279)
Increase (decrease) in cash and cash equivalents		64,916	2,615
Cash and cash equivalents, beginning of period		93,593	61,138
Cash and cash equivalents, end of period		158,509	63,753
Parent/Issuer [Member]
Cash provided by (used in) operating activities		(444,664)	(224,066)
Investing Activities
Acquisition of ICG, net of cash acquired		(2,894,339)
Increase in restricted cash		(5,939)
Capital expenditures		(5,137)	(3,942)
Purchases of investments and advances to affiliates		(777,341)	(12,671)
Cash used in investing activities		(3,682,756)	(16,613)
Financing Activities
Proceeds from the issuance of senior notes		2,000,000	500,000
Proceeds from the sale of common stock		1,267,776
Net increase (decrease) in borrowings under lines of credit and commercial paper program		340,000	(120,000)
Net (payments) and proceeds from other debt		(8,792)	(9,794)
Debt financing costs		(114,563)	(11,901)
Dividends paid		(57,470)	(47,121)
Issuance of common stock under incentive plans		1,628	339
Transactions with affiliates, net		742,906	(123,309)
Cash provided by (used in) financing activities		4,171,485	188,214
Increase (decrease) in cash and cash equivalents		44,065	(52,465)
Cash and cash equivalents, beginning of period		13,713	54,255
Cash and cash equivalents, end of period		57,778	1,790
Guarantor Subsidiaries [Member]
Cash provided by (used in) operating activities		613,179	404,836
Investing Activities
Capital expenditures		(135,640)	(141,825)
Proceeds from dispositions of property, plant and equipment		25,010	178
Purchases of investments and advances to affiliates		(29,872)	(4,069)
Additions to prepaid royalties		(22,163)	(20,880)
Cash used in investing activities		(162,665)	(166,596)
Financing Activities
Contributions from parent		750,386
Payments to retire debt		(604,096)
Transactions with affiliates, net		(596,588)	(238,252)
Cash provided by (used in) financing activities		(450,298)	(238,252)
Increase (decrease) in cash and cash equivalents		216	(12)
Cash and cash equivalents, beginning of period		64	64
Cash and cash equivalents, end of period		280	52
Non-Guarantor Subsidiaries [Member]
Cash provided by (used in) operating activities		302,852	275,910
Investing Activities
Capital expenditures		(75,122)	(75,816)
Proceeds from dispositions of property, plant and equipment		123	74
Additions to prepaid royalties		(3,972)	(2,835)
Cash used in investing activities		(78,971)	(78,577)
Financing Activities
Payments to retire debt			(505,627)
Net increase (decrease) in borrowings under lines of credit and commercial paper program		(56,904)	1,663
Debt financing costs		(24)	(729)
Contribution from noncontrolling interest			891
Transactions with affiliates, net		(146,318)	361,561
Cash provided by (used in) financing activities		(203,246)	(142,241)
Increase (decrease) in cash and cash equivalents		20,635	55,092
Cash and cash equivalents, beginning of period		79,816	6,819
Cash and cash equivalents, end of period		100,451	$ 61,911
Eliminations [Member]
Investing Activities
Purchases of investments and advances to affiliates		750,386
Cash used in investing activities		750,386
Financing Activities
Contributions from parent		(750,386)
Cash provided by (used in) financing activities		$ (750,386)