Alpha Natural Resources 10-K 26 Feb 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Feb. 20, 2015	Jun. 30, 2014
Document and Entity Information [Abstract]
Entity Registrant Name	Alpha Natural Resources, Inc.
Entity Central Index Key	1301063
Document Type	10-K
Document Period End Date	31-Dec-14
Amendment Flag	FALSE
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$448
Entity Common Stock, Shares Outstanding		221,608,152
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY

CONSOLIDATED_STATEMENTS_OF_OPE

CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	0 Months Ended				3 Months Ended												12 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 01, 2014	Aug. 01, 2013	Oct. 31, 2012	Jun. 01, 2012	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Coal revenues																	$3,724,441	$4,257,981	$6,015,696
Freight and handling revenues																	480,841	557,846	761,928
Other revenues																	81,796	137,681	197,260
Total revenues					1,070,615		1,050,592		1,054,098		1,111,773		1,093,700	1,191,094	1,335,123	1,333,591	4,287,078	4,953,508	6,974,884
Costs and expenses:
Cost of coal sales (exclusive of items shown separately below)																	3,381,075	3,980,744	5,004,516
Freight and handling costs																	480,841	557,846	761,928
Other expenses																	67,412	165,485	45,432
Depreciation, depletion and amortization																	750,776	865,021	1,037,575
Amortization of acquired intangibles, net																	39,206	5,056	-70,338
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)																	152,106	158,987	209,788
Asset impairment and restructuring					1,239		11,544		2,590		9,499		12,915	2,017	11,265	11,076	24,872	37,273	1,068,906
Goodwill impairment	308,651	253,102	188,194	1,525,332					308,651					253,102			308,651	253,102	1,713,526
Total costs and expenses																	5,204,939	6,023,514	9,771,333
Loss from operations																	-917,861	-1,070,006	-2,796,449
Other income (expense):
Interest expense																	-288,466	-246,588	-198,147
Interest income																	2,265	3,517	3,373
Marketable Securities, Realized Gain (Loss)																	17,883	0	0
(Loss) gain on early extinguishment of debt																	-2,022	-40,464	773
Equity Method Investment, Realized Gain (Loss) on Disposal					5,999						250,331						256,330	0	0
Miscellaneous income, net																	1,619	23,493	3,306
Total other expense, net																	-12,391	-260,042	-190,695
Loss before income taxes																	-930,252	-1,330,048	-2,987,144
Income tax benefit																	55,291	216,550	549,996
Net income (loss)					($121,661)	[1]	($184,975)	[1]	($512,627)	[1]	($55,698)	[1]	($358,788)	($458,241)	($185,681)	($110,788)	($874,961)	($1,113,498)	($2,437,148)
Basic earnings (loss) per share (in dollars per share)					($0.55)		($0.84)		($2.32)		($0.25)		($1.62)	($2.07)	($0.84)	($0.50)	($3.95)	($5.04)	($11.06)
Diluted earnings (loss) per share (in dollars per share)					($0.55)		($0.84)		($2.32)		($0.25)		($1.62)	($2.07)	($0.84)	($0.50)	($3.95)	($5.04)	($11.06)
Weighted average shares - basic																	221,400,658	220,883,103	220,261,555
Weighted average shares - diluted																	221,400,658	220,883,103	220,261,555
[1]	Net loss includes pretax gains on disposals of equity method investments of $250,331 and $5,999 in the first and fourth quarters of 2014, respectively, and pretax asset impairment and restructuring charges of $9,499, $2,590, $11,544 and $1,239 in the first, second, third and fourth quarters of 2014, respectively. Net loss also includes a goodwill impairment charge of $308,651 in the second quarter of 2014.

CONSOLIDATED_STATEMENTS_OF_COM

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net loss	($874,961)	($1,113,498)	($2,437,148)
Current year actuarial (loss) gain, net of income tax of $12,782, ($88,803) and ($516), for the years ended December 31, 2014, 2013 and 2012, respectively	-217,211	111,960	-651
Prior service (cost) credit for period, net of income tax of $8,170, $0 and ($16,776), for the years ended December 31, 2014, 2013 and 2012, respectively	-13,497	0	28,084
Less: reclassification adjustment for amounts reclassified to earnings due to amortization of net actuarial loss and settlements, net of income tax of ($926), ($1,657) and ($2,898), for the years ended December 31, 2014, 2013 and 2012, respectively	1,483	2,692	4,802
Less: reclassification adjustment for amounts reclassified to earnings due to amortization of prior service credit, net of income tax of $1,686, $1,459 and $241, for the years ended December 31, 2014, 2013 and 2012, respectively	-2,791	-2,360	-400
Unrealized (losses) gains related to cash flow hedges, net of income tax of $0, $625 and ($8,272), for the years ended December 31, 2014, 2013 and 2012, respectively	0	-971	13,812
Less: reclassification adjustment for amounts reclassified to earnings related to settlement of cash flow hedges, net of income tax of $1,469, $1,244 and $6,215, for the years ended December 31, 2014, 2013 and 2012, respectively	-2,341	-1,843	-10,390
Unrealized holding gains (losses) arising during the period, net of income tax of ($6,976), $49 and ($185), for the years ended December 31, 2014, 2013 and 2012, respectively	10,587	-74	309
Less: reclassification adjustment for (gains) losses reclassified to earnings, net of tax of $7,099, ($30), and $200, for the years ended December 31, 2014, 2013 and 2012, respectively	-10,783	46	-334
Total other comprehensive (loss) income, net of tax	-234,553	109,450	35,232
Total comprehensive loss	($1,109,514)	($1,004,048)	($2,401,916)

CONSOLIDATED_STATEMENTS_OF_COM1

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current year actuarial gain (loss) tax	$12,782	($88,803)	($516)
Prior service (cost) credit tax	-8,170	0	-16,776
Reclassification adjustment for amounts reclassified to earnings due to amortization of actuarial net (gain) loss tax	-926	-1,657	-2,898
Reclassification adjustment for amounts reclassified to earnings due to amortization of prior service cost (credit) tax	1,686	1,459	241
Unrealized gains (losses) related to cash flow hedges tax	0	625	-8,272
Reclassification adjustment for amounts reclassified to earnings related to settlement of cash flows hedges tax	1,469	1,244	6,215
Unrealized holding gains (losses) arising during the period tax	-6,976	49	-185
Reclassification adjustment for (gains) losses reclassified to earnings tax	$7,099	($30)	$200

CONSOLIDATED_BALANCE_SHEETS

CONSOLIDATED BALANCE SHEETS (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$741,186	$619,644
Trade accounts receivable, net	314,015	287,655
Inventories, net	237,945	304,863
Available-for-sale Securities, Current	405,169	337,069
Prepaid expenses and other current assets	177,999	439,193
Total current assets	1,876,314	1,988,424
Property, equipment and mine development costs (net of accumulated depreciation and amortization of $2,321,444 and $2,355,425, respectively)	1,425,667	1,798,648
Owned and leased mineral rights and land (net of accumulated depletion of $1,265,901 and $1,167,912, respectively)	6,916,307	7,157,506
Goodwill, net	0	308,651
Other acquired intangibles (net of accumulated amortization of $378,413 and $422,737, respectively)	97,169	158,465
Other non-current assets	420,691	387,564
Total assets	10,736,148	11,799,258
Long-term Debt, Current Maturities	178,251	29,169
Current liabilities:
Trade accounts payable	216,098	234,951
Accrued expenses and other current liabilities	615,200	978,695
Total current liabilities	1,009,549	1,242,815
Long-term debt	3,719,519	3,398,434
Pension and postretirement medical benefit obligations	1,236,986	990,124
Asset retirement obligations	538,008	728,575
Deferred income taxes	773,466	901,552
Other non-current liabilities	471,820	465,892
Total liabilities	7,749,348	7,727,392
Commitments and Contingencies (Note 23)
Stockholders’ Equity
Preferred stock - par value $0.01, 10.0 million shares authorized, none issued	0	0
Common stock - par value $0.01, 400.0 million shares authorized, 233.7 million issued and 221.6 million outstanding at December 31, 2014 and 232.8 million issued and 221.0 million outstanding at December 31, 2013	2,337	2,328
Additional paid-in capital	8,211,122	8,185,222
Accumulated other comprehensive (loss) income	-291,701	-57,148
Treasury stock, at cost: 12.1 million and 11.8 million shares at December 31, 2014 and December 31, 2013, respectively	-273,198	-271,737
Accumulated deficit	-4,661,760	-3,786,799
Total stockholders’ equity	2,986,800	4,071,866
Total liabilities and stockholders’ equity	$10,736,148	$11,799,258

CONSOLIDATED_BALANCE_SHEETS_Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Property, equipment and mine development costs, accumulated depreciation and amortization	$2,321,444	$2,355,425
Owned and leased mineral rights and land, accumulated depletion	1,265,901	1,167,912
Other acquired intangibles, accumulated amortization	$378,413	$422,737
Preferred stock, par value (in dollars per share)	$0.01	$0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Common stock, par value (in dollars per share)	$0.01	$0.01
Common stock, shares authorized	400,000,000	400,000,000
Common stock, shares issued	233,700,000	232,800,000
Common stock, shares outstanding	221,600,000	221,000,000
Treasury stock, shares	12,100,000	11,800,000

CONSOLIDATED_STATEMENTS_OF_CAS

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities:
Net loss	($874,961)	($1,113,498)	($2,437,148)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation, depletion and amortization	750,776	865,021	1,037,575
Amortization of Intangibles Assets, Net	39,206	5,056	-70,338
Amortization of debt issuance costs and accretion of debt discount	54,285	51,217	43,745
Mark-to-market adjustments for derivatives	25,752	6,213	-2,795
Accretion of asset retirement obligations	47,698	60,274	65,548
Stock-based compensation	27,371	25,873	9,881
Employee benefit plans, net	57,972	56,982	72,465
Loss (gain) on early extinguishment of debt	2,022	40,464	-773
Equity Method Investment, Realized Gain (Loss) on Disposal	-256,330	0	0
Marketable Securities, Realized Gain (Loss)	-17,883	0	0
Change in future costs of asset retirement obligations	-107,263	-66,521	-157,173
Deferred income taxes	-40,477	-212,361	-554,575
Gain (Loss) on Disposition of Property Plant Equipment	-19,339	7,851	-4,782
Restructuring Costs and Asset Impairment Charges	24,872	37,273	1,068,906
Goodwill impairment	308,651	253,102	1,713,526
Other, net	10,300	-4,497	-32,406
Changes in operating assets and liabilities:
Trade accounts receivable, net	-26,360	130,511	229,882
Inventories, net	66,589	89,364	93,962
Prepaid expenses and other current assets	98,344	48,717	230,259
Other non-current assets	4,281	3,233	-7,549
Trade accounts payable	-11,540	-30,430	-246,228
Accrued expenses and other current liabilities	-359,310	105,199	-407,128
Pension and postretirement medical benefit obligations	-41,774	-53,527	-53,008
Asset retirement obligations	-55,520	-44,862	-50,313
Other non-current liabilities	8,779	-151,636	-23,114
Net cash (used in) provided by operating activities	-283,859	109,018	518,419
Investing activities:
Capital expenditures	-185,038	-215,661	-402,377
Acquisition of mineral rights under federal lease	-42,130	-42,130	-95,765
Purchases of marketable securities	-679,394	-900,471	-555,096
Sales of marketable securities	697,929	857,000	352,112
Purchase of equity method investments	0	0	-10,100
Proceeds from Sale of Property, Plant, and Equipment	93,033	10,605	38,250
Proceeds from Sale of Equity Method Investments	112,232	0	0
Other, net	1,717	0	0
Net cash used in investing activities	-1,651	-290,657	-672,976
Financing activities:
Proceeds from borrowings on long-term debt	500,000	1,306,677	494,795
Principal repayments of long-term debt	-37,554	-1,176,332	-160,157
Repayments of Long-term Capital Lease Obligations	-19,475	-16,136	-6,490
Debt issuance and modification costs	-28,938	-36,659	-16,361
Common stock repurchases	-1,461	-1,435	-7,507
Other, net	-5,520	-5,555	-4,882
Net cash provided by financing activities	407,052	70,560	299,398
Net increase (decrease) in cash and cash equivalents	121,542	-111,079	144,841
Cash and cash equivalents at beginning of period	619,644	730,723	585,882
Cash and cash equivalents at end of period	741,186	619,644	730,723
Cash paid for interest	197,050	191,178	144,958
Cash paid for income taxes	1,250	2,120	5,038
Cash received for income tax refunds	8,466	389	38,934
Supplemental disclosure of non-cash investing and financing activities:
Capital equipment leases	11,323	8,153	53,192
Capital Expenditures Incurred but Not yet Paid	$26,845	$22,275	$17,652

CONSOLIDATED_STATEMENTS_OF_STO

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $)	Total	Common Stock	Additional Paid-in Capital	Treasury Stock at Cost	Accumulated Other Comprehensive Income (Loss)	Retained Earnings (Accumulated Deficit)
In Thousands, except Share data, unless otherwise specified
Balance at Dec. 31, 2011	$7,375,044	$2,310	$8,073,512	($262,795)	($201,830)	($236,153)
Balance (in shares) at Dec. 31, 2011		231,023,000
Accumulated Other Comprehensive Income [Roll Forward]
Net loss	-2,437,148					-2,437,148
Other comprehensive income (loss), net	35,232				35,232
Exercise of stock options	176	0	176
Exercise of stock options (in shares)		16,000
Stock-based compensation and net issuance of common stock for share vesting	-5,489	12	2,006	-7,507
Stock-based compensation and net issuance of common stock for share vesting (in shares)		1,195,000
Balance at Dec. 31, 2012	4,967,815	2,322	8,075,694	-270,302	-166,598	-2,673,301
Balance (in shares) at Dec. 31, 2012		232,234,000
Accumulated Other Comprehensive Income [Roll Forward]
Net loss	-1,113,498					-1,113,498
Other comprehensive income (loss), net	109,450				109,450
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt	83,131		83,131
Stock-based compensation and net issuance of common stock for share vesting	24,968	6	26,397	-1,435
Stock-based compensation and net issuance of common stock for share vesting (in shares)		578,000
Balance at Dec. 31, 2013	4,071,866	2,328	8,185,222	-271,737	-57,148	-3,786,799
Balance (in shares) at Dec. 31, 2013	221,000,000	232,812,000
Accumulated Other Comprehensive Income [Roll Forward]
Net loss	-874,961					-874,961
Other comprehensive income (loss), net	-234,553				-234,553
Stock-based compensation and net issuance of common stock for share vesting	24,448	9	25,900	-1,461
Stock-based compensation and net issuance of common stock for share vesting (in shares)		922,000
Balance at Dec. 31, 2014	$2,986,800	$2,337	$8,211,122	($273,198)	($291,701)	($4,661,760)
Balance (in shares) at Dec. 31, 2014	221,600,000	233,734,000

Business_and_Basis_of_Presenta

Business and Basis of Presentation	12 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Basis of Presentation	Business and Basis of Presentation
	Business
	Alpha Natural Resources, Inc. and its consolidated subsidiaries (the “Company” or “Alpha”) are primarily engaged in the business of extracting, processing and marketing steam and metallurgical coal from surface and deep mines, and mainly sell to electric utilities, steel and coke producers, and industrial customers. The Company, through its subsidiaries, is also involved in marketing coal produced by others to supplement its own production and, through blending, provides its customers with coal qualities beyond those available from its own production.
	At December 31, 2014, the Company’s coal operations consisted of 45 deep and 15 surface mines located in Virginia, West Virginia, Pennsylvania, Kentucky and Wyoming. At December 31, 2014, the Company had approximately 8,900 employees, of which 11% are affiliated with union representation with the United Mine Workers of America (“UMWA”). The Company’s union represented employees are primarily located in Virginia, West Virginia and Pennsylvania.
	On December 30, 2014, the Company announced that its subsidiary AMFIRE Mining Company, LLC had completed the divestiture of substantially all of its assets to Rosebud Mining Company. The transaction included total consideration of approximately $87,159, including gross cash proceeds of $75,134 and the assumption of certain liabilities. The assets, which included ten mines and four preparation plants and loadouts, were located in Pennsylvania. The Company recognized a gain in cost of coal sales of $9,777 on the sale.
	Basis of Presentation
	The consolidated financial statements include Alpha and its majority owned and controlled subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.
	Reclassifications
	Certain amounts in the 2013 and 2012 Consolidated Statements of Cash Flows have been reclassified to conform to the current year presentation.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies
	Use of Estimates
	The Company’s consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The preparation of the Company’s consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include inventories; mineral reserves; allowance for non-recoupable advanced mining royalties; asset impairments; reclamation obligations; pensions, postemployment, postretirement medical and other employee benefit obligations; useful lives for depreciation, depletion, and amortization; reserves for workers’ compensation and black lung claims; current and deferred income taxes; reserves for contingencies and litigation; and fair value of financial instruments. Estimates are based on facts and circumstances believed to be reasonable at the time; however, actual results could differ from those estimates.
	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash held with reputable depository institutions and highly liquid, short-term investments with original maturities of three months or less. Cash and cash equivalents are stated at cost, which approximates fair market value. The Company’s cash equivalents consist of money market funds that are maintained in highly rated funds at December 31, 2014.
	Marketable Securities
	The Company classifies its marketable securities as trading or available-for-sale. These securities are recorded initially at cost and adjusted to fair value at each reporting date. Unrealized gains and losses resulting from fair value adjustments to available-for-sale securities are classified as a separate component of stockholders’ equity. Unrealized gains and losses resulting from fair value adjustments to trading securities are recorded in current period earnings or loss. Realized gains and losses on available-for-sale securities are computed using the specific identification method. Marketable securities with maturities of one year or less are reported in short-term marketable securities. Marketable securities with maturities of greater than one year are reported in other non-current assets. See Note 7 for further disclosures related to marketable securities.
	Trade Accounts Receivable and Allowance for Doubtful Accounts
	Trade accounts receivable are recorded at the invoiced amount and do not bear interest. The allowance for doubtful accounts is the Company’s best estimate of the amount of probable credit losses in the Company’s existing accounts receivable. The Company establishes provisions for losses on accounts receivable when it is probable that all or part of the outstanding balance will not be collected. The Company regularly reviews its accounts receivable balances and establishes or adjusts the allowance as necessary primarily using the specific identification method. The allowance for doubtful accounts was $5,701 and $6,206 at December 31, 2014 and 2013, respectively. Account balances are written off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote.
	Inventories
	Coal inventories are stated at the lower of average cost or market. The cost of coal inventories is determined based on average cost of production, which includes all costs incurred to extract, transport and process the coal. Market represents the estimated replacement cost, subject to a floor and ceiling, which considers the future sales price of the product as well as remaining estimated preparation and selling costs. Coal is reported as inventory at the point in time the coal is extracted from the mine.
	Material and supplies inventories are valued at average cost, less an allowance for obsolete and surplus items.
	Deferred Longwall Move Expenses
	The Company defers the direct costs, including labor and supplies, associated with moving longwall equipment and the related equipment refurbishment costs in prepaid expenses and other current assets. These deferred costs are amortized on a units-of-production basis into cost of coal sales over the life of the subsequent panel of coal mined by the longwall equipment. See Note 8 for further disclosures related to deferred longwall move expenses.
	Advanced Mining Royalties
	Lease rights to coal reserves are often acquired in exchange for royalty payments. Advance mining royalties are advance payments made to lessors under terms of mineral lease agreements that are recoupable against future production royalties. These advance payments are deferred and charged to operations as the coal reserves are mined. The Company regularly reviews recoverability of advance mining royalties and establishes or adjusts the allowance for advance mining royalties as necessary using the specific identification method. Advance royalty balances are generally charged off against the allowance when they are no longer recoupable.
	The changes in the allowance for advance mining royalties were as follows:
	Balance at December 31, 2011	$	20,373
	Provision for non-recoupable advance mining royalties	8,913
	Write-offs of advance mining royalties	(1,484		)
	Balance at December 31, 2012	27,802
	Provision for non-recoupable advance mining royalties	3,425
	Write-offs of advance mining royalties	(3,883		)
	Balance at December 31, 2013	27,344
	Provision for non-recoupable advance mining royalties	12,767
	Write-offs of advance mining royalties	(6,339		)
	Balance at December 31, 2014	$	33,772
	Property, Equipment and Mine Development Costs
	Costs for mine development incurred to expand capacity of operating mines or to develop new mines are capitalized and charged to operations on the units-of-production method over the estimated proven and probable reserve tons directly benefiting from the capital expenditures. Mine development costs include costs incurred for site preparation and development of the mines during the development stage less any incidental revenue generated during the development stage. Mobile mining equipment and other fixed assets are stated at cost and depreciated on a straight-line basis over estimated useful lives ranging from one to 20 years. Leasehold improvements are amortized using the straight-line method, over the shorter of the estimated useful lives or term of the lease. Major repairs and betterments that significantly extend original useful lives or improve productivity are capitalized and depreciated over the period benefited. Maintenance and repairs are expensed as incurred. When equipment is retired or disposed, the related cost and accumulated depreciation are removed from the respective accounts and any profit or loss on disposal is recognized in cost of coal sales.
	Owned and Leased Mineral Rights and Land
	Costs to obtain owned and leased mineral rights are capitalized and amortized to operations as depletion expense using the units-of-production method. Only proven and probable reserves are included in the depletion base. Depletion expense is included in depreciation, depletion and amortization on the accompanying Consolidated Statements of Operations and was $230,740, $266,642, and $325,999 for the years ended December 31, 2014, 2013, and 2012, respectively.
	Acquired Intangibles
	Application of acquisition accounting resulted in the recognition of assets for above market-priced coal supply and transportation agreements and liabilities for below market-priced coal supply agreements on the date of the acquisitions. The coal supply and transportation agreements were valued based on the present value of the difference between the expected net contractual cash flows based on the stated contract terms, and the estimated net contractual cash flows derived from applying forward market prices at the acquisition dates for new contracts of similar terms and conditions. The coal supply and transportation agreement assets and liabilities are being amortized over the actual amount of tons shipped under each contract. Coal supply and transportation agreement assets are reported in other acquired intangibles and coal supply agreement liabilities are reported in other non-current liabilities in the Consolidated Balance Sheets.
	In addition, the application of acquisition accounting also resulted in the Company recording intangible assets related to mining permits and covenants not-to-compete, which are reported in other acquired intangibles in the Consolidated Balance Sheets. Amortization of other acquired intangible assets was $61,295, $71,867, and $113,750 of expense and amortization of coal supply agreement liabilities was a credit to expense of ($22,089), ($66,811), and ($184,088), equating to a net expense (credit) of $39,206, $5,056 and ($70,338) for the years ended December 31, 2014, 2013 and 2012, respectively, which is reported as amortization of acquired intangibles, net in the Consolidated Statements of Operations. Future net amortization expense related to acquired intangibles is expected to be as follows:
	2015	$	32,304
	2016	24,522
	2017	5,353
	2018	(357		)
	2019	(243		)
	Thereafter	3,432
	Total net future amortization expense	$	65,011
	Asset Impairment and Disposal of Long-Lived Assets
	Long-lived assets, such as property, equipment, mine development costs, owned and leased mineral rights and purchased intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset groups may not be recoverable. Recoverability of assets or asset groups to be held and used is measured by a comparison of the carrying amount of an asset or asset group to the estimated undiscounted future cash flows expected to be generated by the asset or asset group. If the carrying amount of an asset or asset group exceeds its estimated future cash flows, an impairment charge is recognized equal to the amount by which the carrying amount of the asset or asset group exceeds the fair value of the asset or asset group. Assets to be disposed would separately be presented in the balance sheet and reported at the lower of the carrying amount or fair value less costs to sell, and would no longer be depreciated. The assets and liabilities of a disposal group classified as held for sale would be presented separately in the Consolidated Balance Sheets. See Note 10 for further disclosures related to asset impairments.
	Goodwill
	Goodwill represents the excess of the purchase price over the fair value of the net identifiable tangible and intangible assets of acquired companies. Goodwill is not amortized; instead, it is tested for impairment annually or more frequently if indicators of impairment exist. The Company performs its goodwill impairment testing as of October 31 of each year or sooner if indicators of impairment are present. During 2014, 2013 and 2012, the Company performed interim goodwill impairment tests as of June 1, 2014, February 28, 2014, August 1, 2013 and June 1, 2012.
	The Company first assesses goodwill on a qualitative basis. If the qualitative assessment indicates that an impairment potentially exists, then the Company tests its goodwill for impairment using a fair value approach at the reporting unit level in two steps. Step one compares the fair value of each reporting unit to its carrying amount. If step one indicates that the carrying value of a reporting unit exceeds its fair value, the second step is performed to measure the amount of impairment, if any. Goodwill impairment exists when the estimated implied fair value of goodwill is less than its carrying value. See Note 11 for further disclosures related to goodwill.
	Asset Retirement Obligations
	Minimum standards for mine reclamation have been established by various regulatory agencies and dictate the reclamation requirements at the Company’s operations. The Company’s asset retirement obligations consist principally of costs to reclaim acreage disturbed at surface operations, estimated costs to reclaim support acreage, treat mine water discharge and perform other related functions at underground mines. The Company records these reclamation obligations at fair value in the period in which the legal obligation associated with the retirement of the long-lived asset is incurred. Changes to the liability at operations that are not currently being reclaimed are offset by increasing or decreasing the carrying amount of the related long-lived asset. Changes to the liability at operations that are currently being reclaimed are recorded to cost of coal sales. Over time, the liability is accreted and any capitalized cost is depreciated over the useful life of the related asset. To settle the liability, the obligation is paid, and to the extent there is a difference between the liability and the amount of cash paid, a gain or loss upon settlement is recorded. The Company annually reviews its estimated future cash flows for its asset retirement obligations. See Note 15 for further disclosures related to asset retirement obligations.
	Income Taxes
	The Company recognizes deferred tax assets and liabilities using enacted tax rates for the effect of temporary differences between the book and tax basis of recorded assets and liabilities. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that some portion or all of the deferred tax asset will not be realized. In evaluating our ability to recover our deferred tax assets within the jurisdiction in which they arise, we consider all available positive and negative evidence, including the scheduled reversals of deferred tax liabilities, projected future taxable income, taxable income available via carryback to prior years, tax planning strategies, and results of recent operations. Due to the significant negative evidence of cumulative losses in recent years, the Company is unable to utilize estimates of future earnings to support the realization of its deferred tax assets. Therefore, the company is currently relying primarily on income resulting from expected future deferred tax liability reversals, along with carryback opportunities and prudent tax strategies to support the realization of deferred tax assets. If deferred tax assets increase relative to our deferred tax liabilities or circumstances change regarding the reversal patterns of existing deferred balances, the Company would be required to establish additional valuation allowances. See Note 19 for further disclosures related to income taxes.
	Revenue Recognition
	The Company earns revenues primarily through the sale of coal, but also earns other revenues from sales of parts, equipment, filters, rebuild and refurbishment services, sales of natural gas and intercontinental commodity transportation services. With the exception of intercontinental commodity transportation services revenue, the Company recognizes revenue using the following general revenue recognition criteria: 1) persuasive evidence of an arrangement exists; 2) delivery has occurred or services have been rendered; 3) the price to the buyer is fixed or determinable; and 4) collectability is reasonably assured. Revenue from intercontinental commodity transportation services is recognized on a ratable basis over the period of time in which transportation services are provided.
	Delivery on our coal sales is determined to be complete for revenue recognition purposes when title and risk of loss has passed to the customer in accordance with stated contractual terms and there are no other future obligations related to the shipment. For domestic shipments, title and risk of loss generally passes as the coal is loaded into transport carriers for delivery to the customer. For international shipments, title generally passes at the time coal is loaded onto the shipping vessel.
	Freight and handling costs paid to third-party carriers and invoiced to coal customers are recorded as freight and handling costs and freight and handling revenues, respectively.
	Deferred Financing Costs
	The costs to obtain new debt financing or amend existing financing agreements are generally deferred and amortized to interest expense over the life of the related indebtedness or credit facility using the effective interest method. Unamortized deferred financing costs are included in other non-current assets in the Consolidated Balance Sheets.
	Workers’ Compensation and Pneumoconiosis (Black Lung) Benefits
	Workers’ Compensation
	The Company is self-insured for workers’ compensation claims at certain of its operations and is covered by third-party insurance providers at other locations. The liabilities for workers’ compensation claims that are self-insured by the Company are estimates of the ultimate losses incurred based on the Company’s experience, and include a provision for incurred but not reported losses. Adjustments to the probable ultimate liabilities are made annually based on an actuarial study and adjustments to the liability are recorded based on the results of this study. These obligations are included in the Consolidated Balance Sheets as accrued expenses and other current liabilities and other non-current liabilities. See Note 20 for further disclosures related to workers’ compensation liabilities.
	Black Lung Benefits
	The Company is required by federal and state statutes to provide benefits to employees for awards related to black lung. The Company is self-insured at certain locations and covered by a third party insurance provider at other locations. Charges are made to operations for self-insured black lung claims, as determined by an independent actuary at the present value of the actuarially computed liability for such benefits over the employee’s applicable term of service. The Company recognizes in its balance sheet the amount of the Company’s unfunded Accumulated Benefit Obligation (“ABO”) at the end of the year. Amounts recognized in accumulated other comprehensive income (loss) are adjusted out of accumulated other comprehensive income (loss) when they are subsequently recognized as components of net periodic benefit cost. See Note 20 for further disclosures related to black lung benefits.
	Pension and Other Postretirement Benefits
	The Company is required to recognize the overfunded or underfunded status of a defined benefit pension plan as an asset or liability in its Consolidated Balance Sheets and to recognize changes in that funded status in the year in which the changes occur through other comprehensive income (loss). The Company is required to measure plan assets and benefit obligations as of the date of the Company’s fiscal year-end balance sheet and provide the required disclosures as of the end of each fiscal year.
	The Company accounts for health care benefits provided for current and certain retired employees and their dependents by accruing the cost of such benefits over the service lives of employees. Unrecognized actuarial gains and losses are amortized over the estimated average remaining service period for active employees and over the estimated average remaining life for retirees. The Company recognizes in its Consolidated Balance Sheets the amount of the Company’s unfunded Accumulated Postretirement Benefit Obligation (“APBO”) at the end of the year. Amounts recognized in accumulated other comprehensive income (loss) are adjusted out of accumulated other comprehensive income (loss) when they are subsequently recognized as components of net periodic benefit cost.
See Note 20 for further disclosures related to pension and other postretirement benefits.
Earnings Per Share
Basic earnings per share is computed by dividing net income by the weighted-average number of outstanding common shares for the period. Diluted earnings per share reflects the potential dilution that could occur if instruments that may require the issuance of common shares in the future were settled and the underlying common shares were issued. Diluted earnings per share is computed by increasing the weighted-average number of outstanding common shares computed in basic earnings per share to include the additional common shares that would be outstanding after issuance and adjusting net income for changes that would result from the issuance. Only those securities that are dilutive are included in the calculation. See Note 5 for further disclosures related to earnings per share.
Stock-Based Compensation
The Company recognizes expense for stock-based compensation awards based on the estimated grant-date fair value. For all grants, the amount of compensation expense to be recognized is adjusted for an estimated forfeiture rate which is based in part on historical data and other relevant factors. Compensation expense for awards with cliff vesting provisions is recognized on a straight-line basis from the measurement date through the vesting date. Compensation expense for awards with graded vesting provisions is recognized using the accelerated attribution method. See Note 21 for further disclosures related to stock-based compensation arrangements.
Derivative Instruments and Hedging Activities
Derivative financial instruments are recognized as either assets or liabilities in the Consolidated Balance Sheets and measured at fair value. On the date a derivative instrument is entered into, the Company may designate a qualifying derivative instrument as a hedge of the variability of cash flows to be received or paid related to a recognized asset or liability or forecasted transaction (cash flow hedge). The Company formally documents all relationships between hedging instruments and hedged items, as well as its risk-management objective and strategy for undertaking various hedge transactions. This process includes linking all derivatives that are designated as cash flow hedges to specific firm commitments or forecasted transactions. The Company also formally assesses both at the hedge’s inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in cash flows of the related hedged items. When it is determined that a derivative is not highly effective as a hedge or that it has ceased to be a highly effective hedge, the Company discontinues hedge accounting prospectively and records all future changes in fair value in current period earnings or losses.
For derivative instruments that have not been designated as cash flow hedges, changes in fair value are recorded in current period earnings or losses. For derivative instruments that have been designated as cash flow hedges, the effective portion of the changes in fair value are recorded in accumulated other comprehensive income (loss) and any portion that is ineffective is recorded in current period earnings or losses. Amounts recorded in accumulated other comprehensive income (loss) are reclassified to earnings or losses in the period the underlying hedged transaction affects earnings or when the underlying hedged transaction is probable of not occurring. See Note 18 for further disclosures related to derivative financial instruments and hedging activities.
Equity Method Investments
Investments in unconsolidated affiliates that the Company has the ability to exercise significant influence over, but not control, the affiliate’s operating activities are accounted for under the equity method of accounting. Under the equity method of accounting, the Company records its proportionate share of the entity’s net income or loss at each reporting period in the Consolidated Statements of Operations in miscellaneous income, net, with a corresponding entry to increase or decrease the carrying value of the investment.
New Accounting Pronouncements
On April 10, 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity (“ASU 2014-08”), which changes the criteria for reporting discontinued operations and requires additional disclosures about discontinued operations. The standard requires that an entity report as a discontinued operation only a disposal that represents a strategic shift in operations that has a major effect on its operations and financial results. ASU 2014-08 is effective prospectively for new disposals that occur within annual periods beginning on or after December 15, 2014. Early adoption is permitted and the Company adopted ASU 2014-08 during the year ended December 31, 2014. Adoption of the standard did not have a material impact on the Company's results of operations.
On May 28, 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”), which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. ASU 2014-09 will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for the Company on January 1, 2017. Early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company has not yet selected a transition method and is still evaluating the effect of the standard on its ongoing financial reporting.
On June 19, 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period (“ASU 2014-12”). The standard requires a reporting entity to treat a performance target that affects vesting and that could be achieved after the requisite service
period as a performance condition. ASU 2014-12 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted and the Company adopted ASU 2014-12 during the year ended December 31, 2014. Adoption of the standard did not have a material impact on the Company's results of operations.

Mergers_and_Acquisitions

Mergers and Acquisitions	12 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
Mergers and Acquisitions	Mergers and Acquisitions
	On June 1, 2011, the Company completed its acquisition of 100% of the outstanding common stock of Massey Energy Company (“Massey”), a coal producer with operations located primarily in Virginia, West Virginia, and Kentucky.
	The Consolidated Statements of Operations include acquisition related expenses (on a pre-tax basis) of $34,736 in cost of coal sales, $11,418 in selling, general and administrative, and ($32,418) of net other expenses for the year ending December 31, 2012. Expenses included in cost of coal sales consisted of $3,968 related to the impact of acquisition accounting and related fair value adjustments to coal inventory, $1,468 of expenses for benefit integration activities and employee severance, and $29,300 of expenses for contractual settlement-related matters for the year ending December 31, 2012. Expenses included in selling, general and administrative were $10,209 for professional fees related to legal, financing and integration services and $1,209 in expenses for benefits alignment and employee severance for the year ending December 31, 2012. The net other expense of ($32,418) for the year ending December 31, 2012 was recorded for contract-related matters related to coal contracts assumed from Massey.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income	12 Months Ended
	Dec. 31, 2014
Accumulated Other Comprehensive Income [Abstract]
Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss)
	The following tables summarize the changes to accumulated other comprehensive income (loss) during the years ended December 31, 2014, 2013, and 2012:
		Balance December 31, 2013			Other comprehensive			Amounts reclassified			Balance
					income (loss) before reclassifications			from accumulated other comprehensive income (loss)			31-Dec-14
	Employee benefit costs	$	(59,102	)	$	(230,708	)	$	(1,308	)	$	(291,118	)
	Cash flow hedges	1,941			—			(2,341		)	(400		)
	Available-for-sale marketable securities	13			10,587			(10,783		)	(183		)
		$	(57,148	)	$	(220,121	)	$	(14,432	)	$	(291,701	)
		Balance December 31, 2012			Other comprehensive			Amounts reclassified			Balance
					income (loss) before reclassifications			from accumulated other comprehensive income (loss)			31-Dec-13
	Employee benefit costs	$	(171,394	)	$	111,960		$	332		$	(59,102	)
	Cash flow hedges	4,755			(971		)	(1,843		)	1,941
	Available-for-sale marketable securities	41			(74		)	46			13
		$	(166,598	)	$	110,915		$	(1,465	)	$	(57,148	)
		Balance December 31, 2011			Other comprehensive			Amounts reclassified			Balance
					income (loss) before reclassifications			from accumulated other comprehensive income (loss)			31-Dec-12
	Employee benefit costs	$	(203,229	)	$	27,433		$	4,402		$	(171,394	)
	Cash flow hedges	1,333			13,812			(10,390		)	4,755
	Available-for-sale marketable securities	66			309			(334		)	41
		$	(201,830	)	$	41,554		$	(6,322	)	$	(166,598	)
	The following table summarizes the amounts reclassified from accumulated other comprehensive income (loss) and the Consolidated Statement of Operations line items affected by the reclassification during the years ended December 31, 2014, 2013, and 2012:
	Details about accumulated other comprehensive income (loss) components	Amounts reclassified from accumulated other comprehensive income (loss)									Affected line item in the Consolidated Statements of Operations
		Year Ended December 31,
		2014			2013			2012
	Employee benefit costs:
	Amortization of actuarial loss	$	258		$	4,561		$	6,493		(1)
	Amortization of prior service credit	(4,477		)	(3,819		)	(641		)	(1)
	Other	2,151			(212		)	1,207			(1)
	Total before income tax	(2,068		)	530			7,059
	Income tax expense (benefit)	760			(198		)	(2,657		)	Income tax benefit
	Total, net of income tax	$	(1,308	)	$	332		$	4,402
	Cash flow hedges:
	Commodity swaps-coal	$	(4,189	)	$	(4,111	)	$	(1,865	)	Coal revenues
	Commodity swaps-diesel fuel	379			2,777			(10,256		)	Cost of coal sales
	Commodity swaps-natural gas	—			(1,865		)	(4,484		)	Other revenues
	Commodity options-natural gas	—			112			—			Other revenues
	Total before income tax	(3,810		)	(3,087		)	(16,605		)
	Income tax benefit	1,469			1,244			6,215			Income tax benefit
	Total, net of income tax	$	(2,341	)	$	(1,843	)	$	(10,390	)
	Available-for-sale marketable securities:
	Realized gains (losses)	$	(17,882	)	$	76		$	(534	)	Gain on sales of marketable equity securities (2014), Interest income (2013 and 2012)
	Income tax expense (benefit)	7,099			(30		)	200			Income tax benefit
	Total, net of income tax	$	(10,783	)	$	46		$	(334	)
	(1) These accumulated other comprehensive income (loss) components are included in the computation of net periodic benefit costs for pension, other postretirement benefit plans and black lung. See Note 20.

Earnings_Per_Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share
	The number of shares used to calculate basic earnings per common share is based on the weighted average number of the Company’s outstanding common shares during the respective periods. The number of shares used to calculate diluted earnings per common share is based on the number of common shares used to calculate basic earnings per share plus the dilutive effect of stock options and other stock-based instruments held by the Company’s employees and directors during each period, the Company’s outstanding 4.875% convertible senior notes due 2020 (the “4.875% Convertible Notes”), 3.75% convertible senior notes due 2017 (the “3.75% Convertible Notes”), 2.375% convertible senior notes due 2015 (the “2.375% Convertible Notes”), and 3.25% convertible senior notes due 2015 issued by Alpha Appalachia Holdings, Inc. (the “3.25% Convertible Notes”). The 4.875% Convertible Notes, 3.75% Convertible Notes, 2.375% Convertible Notes and 3.25% Convertible Notes become dilutive for earnings per common share calculations in certain circumstances and in specified periods. The shares that would be issued to settle the conversion or conversion spread are included in the diluted earnings per common share calculation when the conversion option is in the money or the notes are otherwise convertible, and the effect is dilutive. In periods of net loss, the number of shares used to calculate diluted earnings per share is the same as basic earnings per share.

Inventories_net

Inventories, net	12 Months Ended
	Dec. 31, 2014
Inventory, Net [Abstract]
Inventories, net	Inventories, net
	Inventories, net consisted of the following:
		December 31,
		2014		2013
	Raw coal	$	38,301	$	39,830
	Saleable coal	121,590		171,240
	Materials, supplies and other, net	78,054		93,793
	Total inventories, net	$	237,945	$	304,863

Marketable_Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	Marketable Securities
	In 2010, the Company entered into a 50/50 joint venture (the “Alpha Shale JV”) with Rice Drilling C LLC, a wholly owned subsidiary of Rice Drilling B LLC, in order to develop a portion of Alpha’s Marcellus Shale natural gas holdings in southwest Pennsylvania. On December 6, 2013, the Company, Rice Drilling C LLC and Rice Energy Inc. (“Rice Energy”) entered into a transaction agreement (the “Transaction Agreement”). Pursuant to the Transaction Agreement, the Company agreed to sell its 50% interest in the Alpha Shale JV to Rice Energy in exchange for total consideration of $300,000, consisting of $100,000 of cash and $200,000 of shares of Rice Energy common stock, based upon the price of Rice Energy’s common stock in its initial public offering (the “Offering”). On January 29, 2014, Rice Energy completed the Offering, and on the same date, issued the Company 9,523,810 shares of common stock and paid $100,000 in cash. The sale of the Company's interest in Alpha Shale resulted in a gain of $250,330 in the first quarter of 2014. During 2014, the Company sold approximately 3.5 million shares of Rice Energy common stock in exchange for $90,882 of cash and recorded a gain of $17,883. The Rice Energy common stock is accounted for as an available for sale marketable security and reported within other non-current assets on the Consolidated Balance Sheet as of December 31, 2014.
	Short-term marketable securities consisted of the following:
		December 31, 2014
				Unrealized
		Cost		Gain		Loss			Fair value
	Short-term marketable securities:
	U.S. treasury and agency securities (a)	$	80,087	$	13	$	(7	)	$	80,093
	Corporate debt securities (a)	325,202		5		(131		)	325,076
	Total short-term marketable securities	$	405,289	$	18	$	(138	)	$	405,169
		31-Dec-13
				Unrealized
		Cost		Gain		Loss			Fair value
	Short-term marketable securities:
	U.S. treasury and agency securities (a)	$	81,484	$	17	$	(4	)	$	81,497
	Corporate debt securities (a)	255,567		49		(44		)	255,572
	Total short-term marketable securities	$	337,051	$	66	$	(48	)	$	337,069
	(a)	Unrealized gains and losses are recorded as component of stockholders’ equity.
	Long-term marketable securities included in other non-current assets, consisted of the following:
		December 31, 2014
				Unrealized
		Cost		Gain		Loss			Fair value
	Long-term marketable securities:
	Corporate equity securities (a)	$	127,001	$	—	$	(181	)	$	126,820
	Money market and mutual funds held in rabbi trust (b)	7,433		4,661		(1,987		)	10,107
	Total long-term securities	$	134,434	$	4,661	$	(2,168	)	$	136,927
		December 31, 2013
				Unrealized
		Cost		Gain		Loss			Fair value
	Long-term marketable securities:
	Money market and mutual funds held in rabbi trust (b)	$	7,261	$	3,637	$	(1,568	)	$	9,330
	(a)	Unrealized gains and losses are recorded as a component of stockholders’ equity.
	(b)	Unrealized gains and losses are recorded in current period earnings.

Prepaid_Expenses_and_Other_Cur

Prepaid Expenses and Other Current Assets	12 Months Ended
	Dec. 31, 2014
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid Expenses and Other Current Assets	Prepaid Expenses and Other Current Assets
	Prepaid expenses and other current assets consisted of the following:
		December 31,
		2014		2013
	Prepaid insurance	$	11,445	$	12,273
	Insurance and indemnification receivables (1)	41,283		195,228
	Notes and other receivables	6,771		10,381
	Deferred income taxes - current	54,451		118,757
	Deferred long wall move expenses	9,309		10,766
	Refundable income taxes	13,532		19,708
	Prepaid freight	20,417		26,445
	Deposits	8,834		13,671
	Other prepaid expenses	11,957		31,964
	Total prepaid expenses and other current assets	$	177,999	$	439,193
	(1)	See Note 13.

Property_Equipment_and_Mine_De

Property, Equipment and Mine Development Costs	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Property, Equipment and Mine Development Costs	Property, Equipment and Mine Development Costs
	Property, equipment, and mine development costs consisted of the following:
		December 31,
		2014		2013
	Plant and mining equipment	$	3,351,521	$	3,731,282
	Mine development	281,594		299,334
	Office equipment, software and other	49,784		61,000
	Construction in progress	64,212		62,457
	Total property, equipment and mine development costs	3,747,111		4,154,073
	Less accumulated depreciation and amortization	2,321,444		2,355,425
	Total property, equipment and mine development costs, net	$	1,425,667	$	1,798,648
	Included in plant and mining equipment are assets under capital leases totaling $100,540 and $92,105 with accumulated depreciation of $43,940 and $26,715 as of December 31, 2014 and December 31, 2013, respectively.
	Depreciation and amortization expense associated with property, equipment and mine development costs was $520,036, $598,380 and $711,577 for the years ended December 31, 2014, 2013 and 2012, respectively.
	Interest costs applicable to major asset additions are capitalized during the construction period. During the year ended December 31, 2012 interest costs of $1,194 were capitalized.
	As of December 31, 2014, the Company had commitments to purchase approximately $22,381 of new equipment, expected to be acquired at various dates in 2015.

Asset_Impairment_and_Restructu

Asset Impairment and Restructuring Asset Impairment and Restructuring	12 Months Ended
	Dec. 31, 2014
Asset Impairment and Restructuring [Abstract]
Asset Impairment and Restructuring	Asset Impairment and Restructuring
	A long-lived asset group that is held and used is reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the long-lived asset or asset group might not be recoverable. As a result of a longer than expected recovery in the metallurgical coal markets and lower production and shipment levels compared with previous estimates and announcements made regarding plans to curtail certain coal mining operations, the Company determined that indicators of impairment with respect to certain of its long-lived assets or asset groups existed during the years ended December 31, 2014, 2013, and 2012. Long-lived assets located in a close geographic area are grouped together for purposes of impairment testing when, after considering revenue and cost interdependencies, circumstances indicate the assets are used together to produce future cash flows. The Company’s asset groups generally consist of the assets and applicable liabilities of one or more mines and preparation plants and associated coal reserves for which cash flows are largely independent of cash flows of other mines, preparation plants and associated coal reserves.
	The Company performed long-lived asset impairment tests as of December 31, 2014, September 30, 2014, June 1, 2014, February 28, 2014, December 31, 2013, August 1, 2013 and June 1, 2012 and determined that the undiscounted cash flows were less than the carrying value for certain asset groups. The Company estimated the fair value of these asset groups using a discounted cash flow analysis utilizing market-place participant assumptions. To the extent that the carrying values of the asset groups exceeded their fair value, the Company recorded an asset impairment charge.
	For the year ended December 31, 2014, the Company recorded severance and other expenses of $15,100 in its Eastern Coal Operations segment and impairment expenses of $9,772 related to certain other non-current assets within the Company’s All Other category.
	For the year ended December 31, 2013, the Company recorded long-lived asset impairment charges totaling $1,890 related to mineral reserves in an asset group in its All Other segment. The Company also recorded severance expenses of $15,756, professional fees and other expenses of $9,627, and reserved $10,000 for other non-current assets which may not be recoverable.
	For the year ended December 31, 2012, the Company recorded long-lived asset impairment charges totaling $1,000,453, of which $994,876 was recorded for asset groups in its Eastern Coal Operations segment and $5,577 was recorded for an asset group in its All Other segment. The long-lived asset impairment charges reduced the carrying values of mineral reserves $714,580, property, plant and equipment $281,357, and other acquired intangibles $4,516. The Company also recorded severance expenses of $33,856, professional fees and other expenses of $13,636, lease termination costs of $13,445 and reserved $7,516 for advanced royalties, deposits and other assets which may not be recoverable.

Goodwill_and_Other_Acquired_In

Goodwill and Other Acquired Intangibles, Net	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Acquired Intangibles, Net	Goodwill and Other Acquired Intangibles, Net
		Balance as of			Impairments			Balance as of
		December 31, 2013						December 31, 2014
	Goodwill:
	Eastern operations	$	3,024,308		$	—		$	3,024,308
	Accumulated impairment losses:
	Eastern operations	$	(2,715,657	)	$	(308,651	)	$	(3,024,308	)
	Goodwill, net:
	Eastern operations	$	308,651		$	(308,651	)	$	—
		Balance as of			Impairments/Disposals			Balance as of
		December 31, 2012						December 31, 2013
	Goodwill:
	Eastern operations	$	3,024,308		$	—		$	3,024,308
	Western operations	53,308			—			53,308
	All other	5,912			(5,912		)	—
	Total goodwill	$	3,083,528		$	(5,912	)	$	3,077,616
	Accumulated impairment losses:
	Eastern operations	$	(2,462,555	)	$	(253,102	)	$	(2,715,657	)
	Western operations	(53,308		)	—			(53,308		)
	All other	—			—			—
	Total accumulated impairment losses	$	(2,515,863	)	$	(253,102	)	$	(2,768,965	)
	Goodwill, net:
	Eastern operations	$	561,753		$	(253,102	)	$	308,651
	Western operations	—			—			—
	All other	5,912			(5,912		)	—
	Total goodwill, net	$	567,665		$	(259,014	)	$	308,651
	The Company performs its annual goodwill impairment test as of October 31 of each year. Interim goodwill impairment tests are performed as conditions warrant. During the first half of 2012, domestic and international coal markets declined as a result of slowing economic activity, fuel switching for electricity generation due to low priced natural gas and U.S. environmental regulations that discourage the use of coal. By June 1, 2012, due to the declining markets and the restructuring actions taken by the Company, the Company updated projections of production volumes and cash operating costs. These events, combined with the Company’s assessment of its long-lived assets for impairment as of June 1, 2012, triggered an interim goodwill impairment test in 2012. Additionally, during 2013, the Company performed an interim goodwill impairment test due primarily to a longer than expected recovery in the metallurgical coal markets and lower production and shipment levels compared with previous estimates and the Company’s assessment of its long-lived assets for impairment as of August 1, 2013. During 2014, the Company performed interim goodwill impairment tests as of June 1 and February 28 due primarily to the Company's assessment of its long-lived assets for impairment as of those dates and continued weakness in the global metallurgical coal markets, which indicated that the fair value of a reporting unit within its eastern coal operations may have been below its carrying value.
	The Company performed its interim and annual goodwill impairment tests using a two-step approach. Step one compares the fair value of each reporting unit to its carrying value. The valuation methodology utilized to estimate the fair value of the reporting units is based on both a market and income approach and is within the range of fair values yielded under each approach. The income approach is based on a discounted cash flow methodology in which expected future net cash flows are discounted to present value, using an appropriate after-tax weighted average cost of capital. The market approach is based on a guideline company and similar transaction method. Under the guideline company method, certain operating metrics from a selected group of publicly traded guideline companies that have similar operations to the Company’s reporting units are used to estimate the fair value of the reporting units. Under the similar transaction method, recent merger and acquisition transactions for companies that have similar operations to the Company’s reporting units are used to estimate the fair value of the Company’s reporting units.
	In step two of the goodwill impairment test, the Company compares the carrying value of goodwill to its implied fair value. In estimating the implied fair value of goodwill at a reporting unit, the Company assigns the fair value of the reporting unit to all of the assets and liabilities associated with the reporting unit as if the reporting unit had been acquired in a business combination.
	As a result of applying the approach discussed above at its interim impairment testing dates of June 1, 2014 and August 1, 2013, its annual impairment testing date of October 31, 2012 and the interim impairment testing date of June 1, 2012, the Company recorded impairment charges of $308,651, $253,102, $188,194, and $1,525,332, respectively, to reduce the carrying value of goodwill to its implied fair value. The impairment charges related to the Company’s Eastern Coal Operations were $308,651, $253,102, $188,194, and $1,472,024 at June 1, 2014, August 1, 2013, October 31, 2012, and June 1, 2012, respectively. The impairment charge related to the Company’s Western Coal Operations was $53,308 at June 1, 2012.
	Other Acquired Intangibles:
		December 31, 2014
		Acquisition value			Accumulated			Balance, net
					amortization
	Assets:
	Above-market coal supply and transportation agreements	$	374,509		$	(305,003	)	$	69,506
	Mining permits	101,073			(73,410		)	27,663
	Total (1)	$	475,582		$	(378,413	)	$	97,169
	Liabilities:
	Below-market coal supply agreements (2)	$	580,327		$	(548,169	)	$	32,158
		December 31, 2013
		Acquisition value			Accumulated			Balance, net
					amortization
	Assets:
	Above-market coal supply and transportation agreements	$	479,361		$	(365,448	)	$	113,913
	Mining permits	101,841			(57,289		)	44,552
	Total (1)	$	581,202		$	(422,737	)	$	158,465
	Liabilities:
	Below-market coal supply agreements (2)	$	605,281		$	(551,035	)	$	54,246
	(1)	Reported as other acquired intangibles in the Consolidated Balance Sheets.
	(2)	Reported in other long-term liabilities in the Consolidated Balance Sheets.

Other_Noncurrent_Assets

Other Non-current Assets	12 Months Ended
	Dec. 31, 2014
Other Assets, Noncurrent [Abstract]
Other Non-current Assets	Other Non-current Assets
	Other non-current assets consisted of the following:
		December 31,
		2014		2013
	Marketable securities - long term (1)	$	136,927	$	9,330
	Unamortized deferred financing costs, net	96,682		94,672
	Advance mining royalties, net	51,530		60,310
	Virginia tax credit, net	21,469		22,124
	Equity method investments (2)	71,224		151,382
	Insurance receivables	20,337		24,281
	Other	22,522		25,465
	Total other non-current assets	$	420,691	$	387,564
	(1)	See Note 7.
	(2)	The equity method investment balances include the company’s Marcellus gas joint venture with EDF Trading Resources, LLC, a fifty percent owner with Alpha.

Accrued_Expenses_and_Other_Cur

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2014
Accounts Payable and Accrued Liabilities, Current [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities
	Accrued expenses and other current liabilities consisted of the following:
		December 31,
		2014		2013
	Wages and employee benefits	$	111,627	$	117,561
	Current portion of asset retirement obligations	102,493		70,851
	Taxes other than income taxes	108,504		123,361
	Interest payable	45,612		22,321
	Current portion of postretirement medical benefit obligations	46,678		46,678
	Deferred revenue	27,488		41,250
	Litigation (1)	51,280		447,214
	Other	121,518		109,459
	Total accrued expenses and other current liabilities	$	615,200	$	978,695
	(1) The Company has recorded related receivables of $41,283 and $195,228 from insurance coverage and indemnifications in prepaid expenses and other current assets at December 31, 2014 and 2013, respectively.

LongTerm_Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2014
Long-term Debt, Unclassified [Abstract]
Long-Term Debt	Long-Term Debt
	Long-term debt consisted of the following:
		December 31,
		2014			2013
	2.375% convertible senior notes due 2015	$	44,458		$	65,889
	3.25% convertible senior notes due 2015	109,201			128,182
	3.75% convertible senior notes due 2017	345,000			345,000
	9.75% senior notes due 2018	500,000			500,000
	6.00% senior notes due 2019	800,000			800,000
	4.875% convertible senior notes due 2020	345,000			345,000
	7.50% senior secured second lien notes due 2020	500,000			—
	Term loan due 2020	614,062			620,313
	6.25% senior notes due 2021	700,000			700,000
	Other	61,344			73,305
	Debt discount, net	(121,295		)	(150,086		)
	Total long-term debt	$	3,897,770		$	3,427,603
	Less current portion	(178,251		)	(29,169		)
	Long-term debt, net of current portion	$	3,719,519		$	3,398,434
	Fifth Amended and Restated Credit Agreement
	On September 24, 2014, the Company entered into an amendment and restatement of the Fourth Amended and Restated Credit Agreement (as amended and restated, the “Credit Agreement” or the “Fifth Amended and Restated Credit Agreement”). The amendment, among other things:
	•	extends the maturity of approximately 75% of previous revolving credit facility commitments (the “Extended Maturity Revolver Facility Commitments”) from June 30, 2016 to September 30, 2017, with the remaining approximately 25%, or $276,000, of revolving credit facility commitments expiring, as previously, on June 30, 2016;
	•	reduces the amount of the Extended Maturity Revolver Facility Commitments by 25% to $618,000 and provides for an increase in the interest rate payable to holders of the Extended Maturity Revolver Facility Commitments on borrowings under the revolving credit facility, effective as of the date of the amendment; and
	•	makes other changes to the Fourth Amended and Restated Credit Agreement, including eliminating the interest coverage financial covenant previously scheduled to apply starting in the first quarter of 2016, extending the minimum liquidity covenant through September 30, 2017, accelerating the date by which certain real property is added as collateral and adding provisions to facilitate future extensions and refinancings under the Fifth Amended and Restated Credit Agreement.
	Mandatory Prepayments. The Credit Agreement requires Alpha to prepay outstanding loans, subject to certain exceptions, with (i) 100% of the net cash proceeds (including the fair market value of noncash proceeds) from certain asset sales and condemnation events in excess of the greater of $1,500,000 and 15% of consolidated tangible assets as of the end of each fiscal year, (ii) 100% of the aggregate gross proceeds (including the fair market value of noncash proceeds) from certain Intracompany Disposals (as defined in the Credit Agreement) exceeding $500,000 during the term of the Credit Agreement and (iii) 100% of the net cash proceeds from any incurrence or issuance of certain debt, other than debt permitted under the Credit Agreement. Mandatory prepayments will be applied first to the Term Loan Facility and thereafter to reductions of the commitments under the Revolving Facility. If at any time the aggregate amount of outstanding revolving loans, swingline loans, unreimbursed letter of credit drawings and undrawn letters of credit under the Revolving Facility exceeds the commitment amount, Alpha will be required to repay outstanding loans or cash collateralize letters of credit in an aggregate amount equal to such excess, with no reduction of the commitment amount.
	Voluntary Prepayments; Reductions in Commitments. Alpha may prepay, in whole or in part, amounts outstanding under the Credit Agreement, with prior notice but without premium or penalty (other than customary “breakage” costs with respect to LIBO rate loans) and in certain minimum amounts. Alpha may also repurchase loans outstanding under the Term Loan Facility pursuant to standard reverse Dutch auction and open market purchase provisions, subject to certain limitations and exceptions.  Alpha may make voluntary reductions to the unutilized commitments of the Revolving Facility from time to time without premium or penalty.
	Guarantees and Collateral. All obligations under the Credit Agreement are unconditionally guaranteed by certain of Alpha’s existing wholly owned domestic subsidiaries, and are required to be guaranteed by certain of Alpha’s future wholly owned domestic subsidiaries. All obligations under the Credit Agreement and certain hedging and cash management obligations with lenders and affiliates of lenders thereunder are secured, subject to certain exceptions, by substantially all of Alpha’s assets and the assets of Alpha’s subsidiary guarantors, in each case subject to exceptions, thresholds and limitations.
	Certain Covenants and Events of Default. The Credit Agreement contains a number of negative covenants that, among other things and subject to certain exceptions, restrict Alpha’s ability and the ability of Alpha’s subsidiaries to:
	•	make investments, loans and acquisitions;
	•	incur additional indebtedness;
	•	incur liens;
	•	consolidate or merge;
	•	sell assets, including capital stock of its subsidiaries;
	•	pay dividends on its capital stock or redeem, repurchase or retire its capital stock or certain of its other indebtedness;
	•	engage in transactions with its affiliates;
	•	materially alter the business it conducts; and
	•	create restrictions on the payment of dividends or other amounts to Alpha from Alpha’s restricted subsidiaries.
	The Credit Agreement also contains customary representations and warranties, affirmative covenants and events of default, including a cross-default provision in respect of any other indebtedness that has an aggregate principal amount exceeding $25,000.
	As of December 31, 2014, the carrying value of the Term Loan Facility was $611,655, net of debt discount of $2,407, with $6,250 classified as current portion of long-term debt. As of December 31, 2013, the carrying value of the Term Loan Facility was $617,460, net of debt discount of $2,853, with $6,250 classified as current portion of long-term debt. There were no borrowings outstanding under the Revolving Facility as of December 31, 2014 or 2013. Letters of credit outstanding at December 31, 2014 and 2013 under the Revolving Facility were $177,249 and $133,975, respectively.
	Fourth Amended and Restated Credit Agreement
	On May 22, 2013, the Company entered into a Fourth Amended and Restated Credit Agreement, which was subsequently amended in October 2013 and May 2014, with the lenders party thereto, the issuing banks party thereto, Citicorp North America, Inc., as administrative agent and as collateral agent, and all other parties thereto from time to time. The Fourth Amended and Restated Credit Agreement amended and restated the Company’s Third Amended and Restated Credit Agreement, dated as of May 19, 2011, as amended June 26, 2012 (the “Third Amended and Restated Credit Agreement”).
	The Fourth Amended and Restated Credit Agreement included a $625,000 senior secured term loan B facility (the “Term Loan Facility”), which matures on May 22, 2020, amortizes in quarterly installments at a rate of 1.0% per year and bears an interest rate at the Company’s option of either LIBOR plus a margin of 2.75% (subject to a LIBOR floor of 0.75%) or an Alternate Base Rate (ABR) plus a margin of 1.75% (subject to an ABR floor of 1.75%). The interest rate in effect as of December 31, 2014 and 2013 was 3.50%. In addition to paying interest on outstanding principal under the Fourth Amended and Restated Credit Agreement, Alpha is required to pay a commitment fee to the lenders under the senior secured revolving facility (the “Revolving Facility”) in respect of the unutilized commitments thereunder. The initial commitment fee is 0.50% per annum, subject to adjustment each fiscal quarter based on Alpha’s consolidated leverage ratio for the preceding fiscal quarter. Alpha must also pay customary letter of credit fees and agency fees.
	The proceeds of the Term Loan Facility were used to repay the entire $525,000 aggregate principal amount of the Company’s outstanding obligations under its term loan A facility under the Third Amended and Restated Credit Agreement, which would have matured on June 30, 2016, with the balance used to pay fees and expenses and for general corporate purposes. The Company recorded a loss on early extinguishment of debt of $9,044, primarily related to certain fees incurred in the transactions and the write off of certain outstanding deferred fees.
	The principal changes to the Third Amended and Restated Credit Agreement effected by the Fourth Amended and Restated Credit Agreement included increasing the previous revolving facility from $1,000,000 to $1,100,000 through its maturity date of June 30, 2016 and modifying the financial covenants by:
	•	modifying the interest coverage ratio covenant from 2.25 to 1.50 through 2013, from 2.50 to 1.50 during 2014 and from 2.50 to 2.00 from 2015 through the maturity date of the revolving credit facility (June 30, 2016);
	•	eliminating the leverage ratio covenant;
	•	extending the applicability of the senior secured leverage ratio of 2.50 through the maturity date of the revolving credit facility; and
	•	reducing the minimum liquidity covenant, which applied until December 31, 2014, from $500,000 to $300,000;
	Additionally, the terms of the Fourth Amended and Restated Credit Agreement (i) further restricted the ability of the Company and its subsidiaries to make investments, loans and acquisitions, incur additional indebtedness, and pay dividends on its capital stock or redeem, repurchase or retire its capital stock; and (ii) require the Company to provide additional collateral to secure the obligations under the Fourth Amended and Restated Credit Agreement, consisting of receivables previously securing the Second Amended and Restated Receivables Purchase Agreement.
	On October 2, 2013, the Company entered into an amendment (“Amendment No. 1”) to the Fourth Amended and Restated Credit Agreement which eliminated the interest coverage ratio through the end of 2014, and modified the interest coverage ratio from 2.00 to 1.25 during 2015 and from 2.00 to 1.50 during the first two quarters of 2016.
	On May 7, 2014, the Company entered into an amendment (“Amendment No. 2”) to the Fourth Amended and Restated Credit Agreement. The principal changes to the Fourth Amended and Restated Credit Agreement effected by Amendment No. 2 include the following: suspending the interest coverage ratio until the first quarter of 2016, replacing the senior secured leverage ratio with a first lien senior secured leverage ratio, reducing the size of the restricted payment basket, extending the minimum liquidity covenant through the end of 2015, increasing by $400,000 the amount of additional debt permitted to be incurred either pursuant to the “accordion” feature of the Fourth Amended and Restated Credit Agreement or a notes offering, and requiring the first $800,000 of additional debt incurred pursuant to the accordion or a notes offering (including the debt represented by the 7.50% senior secured second lien notes due 2020 issued in May 2014) to be unsecured debt or second lien secured debt.
	Indenture and New Senior Secured Second Lien Notes
	On May 20, 2014, Alpha, certain of Alpha’s wholly owned domestic subsidiaries, as guarantors (collectively, the “Guarantors”), and Wilmington Trust, National Association (“Wilmington Trust”), as trustee, entered into an indenture (the “Indenture”) governing Alpha’s newly issued 7.50% senior secured second lien notes due 2020 (the “New Secured Notes”) at 100% of par value. The New Secured Notes pay interest semiannually in arrears on February 1 and August 1 of each year, beginning on February 1, 2015, at a rate of 7.50% per year, and will mature on August 1, 2020.
	The New Secured Notes are guaranteed by each of Alpha’s current and future wholly owned domestic subsidiaries that guarantee Alpha’s obligations under the Credit Agreement. The New Secured Notes are Alpha’s senior secured obligations, ranking equal in right of payment with all of Alpha’s existing and future indebtedness that is not subordinated in right of payment to the New Secured Notes; secured by a second priority lien on Alpha’s assets that secure Alpha’s indebtedness under the Credit Agreement, and thus effectively junior to Alpha’s indebtedness that is permitted to be secured by first priority liens on the collateral securing the New Secured Notes, including indebtedness under the Credit Agreement, and to indebtedness
	secured by assets that are not part of the collateral securing the New Secured Notes, in each case to the extent of the value of the assets securing such indebtedness; senior in right of payment to all of Alpha’s future debt that is subordinated in right of payment to the New Secured Notes; and structurally subordinated to any existing and future indebtedness and other liabilities of any non-guarantor subsidiary.
	Alpha may redeem the New Secured Notes, in whole or in part, at any time prior to August 1, 2016, at a price equal to 100% of the aggregate principal amount of the New Secured Notes plus a “make-whole” premium, plus accrued and unpaid interest, if any, to, but not including, the applicable redemption date. In addition, Alpha may redeem up to 35% of the aggregate principal amount of the New Secured Notes with the net cash proceeds from certain equity offerings, at any time prior to August 1, 2016 at a redemption price equal to 107.5% of the aggregate principal amount of the New Secured Notes, plus accrued and unpaid interest, if any, to, but not including, the applicable redemption date if at least 65% of the aggregate principal amount of New Secured Notes issued under the Indenture remains outstanding after the redemption. Alpha may also redeem the New Secured Notes, in whole or in part, at any time on or after August 1, 2016, at the redemption prices specified in the Indenture, plus accrued and unpaid interest, if any, to, but not including, the applicable redemption date.
	Upon the occurrence of a change of control repurchase event with respect to the New Secured Notes, unless Alpha has exercised its right to redeem the New Secured Notes, Alpha will be required to offer to repurchase each holder’s New Secured Notes at a price equal to 101% of the principal amount thereof, plus accrued and unpaid interest, if any, to, but not including, the date of repurchase.
	The Indenture contains covenants that limit, among other things, Alpha’s ability to:
	•	incur, or permit its subsidiaries to incur, additional debt;
	•	issue, or permit its subsidiaries to issue, certain types of stock;
	•	pay dividends on its or its subsidiaries’ capital stock or repurchase its capital stock;
	•	make certain investments;
	•	enter into certain types of transactions with affiliates;
	•	incur liens on certain assets to secure debt;
	•	limit dividends or other payments by its restricted subsidiaries to it and its other restricted subsidiaries;
•	consolidate, merge or sell all or substantially all of its assets; and
•	make certain payments on its or its subsidiaries’ subordinated debt.
These covenants are subject to a number of important qualifications and exceptions. These covenants may not apply at any time after the New Secured Notes are assigned a credit grade rating of at least BB+ (stable) from Standard & Poor’s Ratings Services and of at least Ba1 (stable) from Moody’s Investors Service, Inc.
Accounts Receivable Securitization Facility
On September 19, 2014, ANR Second Receivables Funding, LLC (“ANR Second Receivables Funding”), a special purpose indirect subsidiary of the Company, entered into a Credit and Security Agreement (the “A/R Facility”) with General Electric Capital Corporation, as a lender, a swing line lender, an LC Lender (as defined therein) and the administrative agent, and Webster Business Credit Corporation, as an LC Lender and as a Lender, and certain financial institutions from time to time parties thereto, as Lenders (as defined therein). Under the A/R Facility, ANR Second Receivables Funding may borrow cash from the Lenders or cause the LC Lenders to issue letters of credit, on a revolving basis, in an amount up to $200,000, subject to certain limitations set forth therein. The funding pursuant to the A/R Facility is available through the earlier of September 19, 2018 or 90 days prior to the earliest scheduled maturity date of: (1) the Fourth Amended and Restated Credit Agreement, with Citicorp North America, Inc. and all other parties thereto from time to time, as such maturity date may be amended from time to time in a manner that meets the requirements set forth in the A/R Facility (which requirements were met by the amendment described above under the caption “Fifth Amended and Restated Credit Agreement”), (2) any successor to, or replacement of, the Fourth Amended and Restated Credit Agreement meeting the requirements set forth in the A/R Facility, or (3) the earliest scheduled maturity date of any obligations for Indebtedness (as defined therein) (a) maturing after December 31, 2015, and (b) having an outstanding principal balance in excess of $100,000 on such 90th day.
The obligations of the Lenders to make cash advances and of the LC Lenders to issue letters of credit pursuant to the A/R Facility are secured by certain trade receivables owned by ANR Second Receivables Funding. The receivables are originated by Alpha Coal Sales Co., LLC (“Alpha Coal Sales”), an indirect subsidiary of the Company and the sole member of ANR Second Receivables Funding, as sales agent on behalf of certain operating subsidiaries of the Company, and arise from the fulfillment of customer contracts entered into by Alpha Coal Sales. The A/R Facility provides that a specified percentage of billed and unbilled receivables meeting certain criteria are eligible to be counted for purposes of determining the amount of financing available to ANR Second Receivables Funding, subject to customary limits and reserves, including limits and reserves based on a dilution rate (calculated using factors including whether any portion of the receivable was reduced, canceled or written-off or is subject to dispute, offset, counterclaim or other defense), a loss rate and certain obligor and payment characteristics of the receivables. On each transfer date during the term of the A/R Facility, Alpha Coal Sales will sell and/or contribute receivables to ANR Second Receivables Funding. Alpha Coal Sales will service those receivables on behalf of ANR Second Receivables Funding and may be required to repurchase receivables in the event of a breach of certain representations or warranties made pursuant to the A/R Facility.
The Lenders and the LC Lenders will be entitled to receive interest payments with respect to the outstanding amount of each advance (including letter of credit participations) made or maintained under the A/R Facility by each Lender or LC Lender during each applicable settlement period. In addition, ANR Second Receivables Funding will pay General Electric Capital Corporation a fee as administrative agent. Certain other fees and expenses are payable to the participating financial institutions. Collections on the receivables, as well as amounts required to remain on deposit in certain accounts under the A/R Facility, will be available to pay the interest, fees and expenses, as well as to collateralize the letters of credit, if required under the A/R Facility, and repay principal on cash advances.
The A/R Facility and related documents contain affirmative, negative and financial covenants customary for financings of this type, including restrictions related to, among other things, liens, payments, merger or consolidation and amendments to the contracts pursuant to which the receivables were originated. The A/R Facility includes termination events customary for facilities of this type (with typical grace periods, where applicable), including, among other things, breaches of covenants, inaccuracies of representations and warranties, bankruptcy and insolvency events, changes in the rate of default, delinquency or dilution of the receivables above specified levels, failure to comply with a springing fixed charge coverage ratio which is only applicable when certain borrowing capacity ratios have been reached, occurrence of a change of control and existence of material judgments. A termination event would permit the administrative agent to terminate the program and enforce any and all rights under the A/R Facility and certain agreements related thereto. Additionally, the A/R Facility contains cross-default provisions, which would allow the administrative agent to terminate the program in the event of non-payment of other material indebtedness when due, and any other event which results in the acceleration of the maturity of material indebtedness.
Although the Lenders and the LC Lenders bear the risk of non-payment by any obligor of the receivables, the Company has agreed to guarantee the performance of its subsidiaries, other than ANR Second Receivables Funding, under the A/R Facility and agreements related to the A/R Facility for the benefit of the Lenders and the LC Lenders.
As of December 31, 2014, letters of credit outstanding were $34,969, no cash borrowing transactions had taken place and $165,031 was available under the A/R Facility.
Convertible Senior Notes
In May 2013, the Company issued $345,000 principal amount of 3.75% Convertible Notes and in December 2013, the Company issued $345,000 principal amount of 4.875% Convertible Notes (the 4.875% Convertible Notes, and together with the 3.75% Convertible Notes, the “Convertible Notes”). The 3.75% Convertible Notes bear interest at a rate of 3.75% per annum, payable semi-annually in arrears on June 15 and December 15 of each year, and will mature on December 15, 2017. The 4.875% Convertible Notes bear interest at a rate of 4.875% per annum, payable semi-annually in arrears on June 15 and December 15 of each year, and will mature on December 15, 2020.
The proceeds from the 3.75% Convertible Notes, together with cash on hand, were used to repurchase $225,787 of the Company’s outstanding 3.25% Convertible Notes and $181,403 of the Company’s outstanding 2.375% Convertible Notes. The Company recorded a loss on early extinguishment of debt of $22,795, primarily related to the write off of outstanding debt discounts. The proceeds from the 4.875% Convertible Notes were used to repurchase $177,093 of the Company’s outstanding 3.25% Convertible Notes and $36,808 of the Company’s outstanding 2.375% Convertible Notes. The Company recorded a loss on early extinguishment of debt of $7,425, primarily related to the write off of outstanding debt discounts.
The Company separately accounts for the liability and equity components of the Convertible Notes in a manner reflective of its’ nonconvertible debt borrowing rate. The related deferred loan costs and discount are being amortized and accreted, respectively, over the terms of the Convertible Notes, and provide for an effective interest rate of 8.49% in the case of the 3.75% Convertible Notes and 9.48% in the case of the 4.875% Convertible Notes. As of December 31, 2014, the carrying amount of the debt component was $302,378 in the case of the 3.75% Convertible Notes and $272,886 in the case of the 4.875% Convertible Notes, and the unamortized debt discount was $42,622 in the case of the 3.75% Convertible Notes and $72,114 in the case of the 4.875% Convertible Notes. As of December 31, 2013, the carrying amount of the debt component was $290,219 in the case of the 3.75% Convertible Notes and $264,283 in the case of the 4.875% Convertible Notes, and the unamortized debt discount was $54,781 in the case of the 3.75% Convertible Notes and $80,717 in the case of the 4.875% Convertible Notes.
The Convertible Notes are the Company’s senior unsecured obligations and rank equally with all of its existing and future senior unsecured indebtedness. The Convertible Notes are guaranteed on a senior unsecured basis by each of the Company’s current and future wholly owned domestic subsidiaries that guarantee the Company’s obligations under its 9.75% senior notes due 2018. The Convertible Notes are effectively subordinated to all of the Company’s existing and future secured indebtedness and all existing and future liabilities of its non-guarantor subsidiaries, including trade payables.
The Convertible Notes are convertible in certain circumstances and in specified periods at an initial conversion rate of 99.0589 shares of common stock per $1 of principal amount of notes in the case of the 3.75% Convertible Notes and 107.0893 shares of common stock per $1 of principal amount of notes in the case of the 4.875% Convertible Notes, subject to adjustment upon the occurrence of certain events set forth in the fourth and fifth supplemental indentures (the “Supplemental Indentures”) to the indenture dated June 1, 2011 (the “Base Indenture” and, together with the Supplemental Indentures, the “Convertible Notes Indentures”) governing the Convertible Notes, equivalent to an initial conversion price of approximately $10.10 per share of common stock in the case of the 3.75% Convertible Notes and $9.34 in the case of the 4.875% Convertible Notes. Upon conversion, the notes may be settled, at the Company’s election, in cash, shares of our common stock or a combination thereof. The Company intends to settle conversions, if any, using a combination of cash and shares.
The Convertible Notes Indentures contain customary terms and covenants, including that upon certain events of default occurring and continuing, either the trustee, Union Bank of California, or the holders of not less than 25% in aggregate principal amount of the Convertible Notes then outstanding may declare the principal of the Convertible Notes and any accrued and unpaid interest thereon immediately due and payable. In the case of certain events of bankruptcy, insolvency or reorganization relating to the Company, the principal amount of the Convertible Notes together with any accrued and unpaid interest thereon will automatically become due and be immediately payable.
The Convertible Notes were not convertible as of December 31, 2014 or 2013 and are classified as long-term debt as of December 31, 2014.
Notes Indenture and the Senior Notes
On June 1, 2011, Alpha, certain of Alpha’s wholly owned domestic subsidiaries (collectively, the “Alpha Guarantors”) and Union Bank, N.A., as trustee, entered into an indenture (the “Base Indenture”) and a first supplemental indenture (the “First Supplemental Indenture” and, together with the Base Indenture, the “Notes Indenture”) governing Alpha’s newly issued 6.00% senior notes due 2019 (the “2019 Notes”) and 6.25% senior notes due 2021 (the “2021 Notes”).
On June 1, 2011, in connection with the Massey Acquisition, Alpha, the Alpha Guarantors, Massey, and certain wholly owned subsidiaries of Massey (the “Massey Guarantors” and together with the Alpha Guarantors the “Guarantors”), and Union Bank, N.A., as trustee, entered into a supplemental indenture (the “Second Supplemental Indenture”) to the Notes Indenture pursuant to which Massey and certain wholly owned subsidiaries of Massey agreed to become additional guarantors for the 2019 Notes and 2021 Notes.
On October 11, 2012, Alpha, the Guarantors and Union Bank, N.A., as trustee, entered into a supplemental indenture (the “Third Supplemental Indenture”) to the Notes Indenture governing Alpha’s newly issued 9.75% senior notes due 2018 (the “2018 Notes” and, together with the 2019 Notes and the 2021 Notes, the “Senior Notes”).
The 2018 Notes bear interest at a rate of 9.75% per annum, payable semi-annually on April 15 and October 15 of each year, beginning on April 15, 2013, and will mature on April 15, 2018. The 2019 Notes bear interest at a rate of 6.00% per annum, payable semi-annually on June 1 and December 1 of each year, beginning on December 1, 2011, and will mature on June 1, 2019. The 2021 Notes bear interest at a rate of 6.25% per annum, payable semi-annually on June 1 and December 1 of each year, beginning on December 1, 2011, and will mature on June 1, 2021.
As of December 31, 2014, the carrying values of the 2018 Notes, 2019 Notes and 2021 Notes were $497,779 (net of discount of $2,221), $800,000 and $700,000, respectively. As of December 31, 2013, the carrying values of the 2018 Notes, 2019 Notes and 2021 Notes were $496,547 (net of discount of $3,453), $800,000 and $700,000, respectively.
Alpha may redeem the 2018 Notes, in whole or in part, at any time prior to maturity, at a price equal to 100.000% of the aggregate principal amount of the 2018 Notes plus a “make-whole” premium, plus accrued and unpaid interest, if any, to, but not including, the applicable redemption date. In addition, Alpha may redeem up to 35% of the aggregate principal amount of the 2018 Notes with the net cash proceeds from certain equity offerings, at any time prior to October 15, 2015, at a redemption price equal to 109.75% of the aggregate principal amount of the 2018 Notes, plus accrued and unpaid interest, if any, to, but not including the applicable redemption date, if at least 65% of the aggregate principal amount of the 2018 Notes originally issued under the Notes Indenture remains outstanding immediately after the redemption and the redemption occurs within 180 days of the date of the closing of such equity offering.
Alpha may redeem the 2019 Notes, in whole or in part, at any time during the twelve months commencing June 1, 2014, at 103.000% of the aggregate principal amount of the 2019 Notes, at any time during the twelve months commencing June 1, 2015, at 101.500% of the aggregate principal amount of the 2019 Notes, and at any time after June 1, 2016 at 100.000% of the aggregate principal amount of the 2019 Notes, in each case plus accrued and unpaid interest, if any, to, but not including, the applicable redemption date.
Alpha may redeem the 2021 Notes, in whole or in part, at any time prior to June 1, 2016, at a price equal to 100.000% of the aggregate principal amount of the 2021 Notes plus a “make-whole” premium, plus accrued and unpaid interest, if any, to, but not including, the applicable redemption date. Alpha may redeem the 2021 Notes, in whole or in part, at any time during the twelve months commencing June 1, 2016, at 103.125% of the aggregate principal amount of the 2021 Notes, at any time during the twelve months commencing June 1, 2017, at 102.083% of the aggregate principal amount of the 2021 Notes, at any time during the twelve months commencing June 1, 2018, at 101.042% of the aggregate principal amount of the 2021 Notes, and at any time after June 1, 2019, at 100.000% of the aggregate principal amount of the 2021 Notes, in each case plus accrued and unpaid interest, if any, to, but not including, the applicable redemption date. In addition, Alpha may redeem up to 35% of the aggregate principal amount of the 2021 Notes with the net cash proceeds from certain equity offerings, at any time prior to June 1, 2016, at a redemption price equal to 106.250% of the aggregate principal amount of the 2021 Notes, plus accrued and unpaid interest, if any, to, but not including the applicable redemption date, provided that at least 65% of the aggregate principal amount of the 2021 notes originally issued under the Notes Indenture remains outstanding after the redemption and the redemption occurs within 180 days of the date of the closing of such equity offering.
Upon the occurrence of a change in control repurchase event with respect to any of the series of the Senior Notes, unless Alpha has exercised its right to redeem those Senior Notes, Alpha will be required to offer to repurchase each holder’s Senior Notes of such series at a price equal to 101% of the principal amount thereof, plus accrued and unpaid interest, if any, to, but not including, the date of repurchase.
The Notes Indenture contains covenants that limit, among other things, Alpha’s ability to:
•incur, or permit its subsidiaries to incur, additional debt;
•issue, or permit its subsidiaries to issue, certain types of stock;
•pay dividends on Alpha’s or its subsidiaries’ capital stock or repurchase Alpha’s common stock;
•make certain investments;
•enter into certain types of transactions with affiliates;
•incur liens on certain assets to secure debt;
•limit dividends or other payments by its restricted subsidiaries to Alpha and its other restricted subsidiaries;
•consolidate, merge or sell all or substantially all of its assets; and
•make certain payments on Alpha’s or its subsidiaries’ subordinated debt.
These covenants are subject to a number of important qualifications and exceptions. These covenants may not apply at any time after the Senior Notes are assigned a credit grade rating of at least BB+ (stable) from Standard & Poor’s Ratings Services and of at least Ba1 (stable) from Moody’s Investor Service, Inc.
3.25% Convertible Senior Notes due 2015
As a result of the Massey Acquisition, the Company became a guarantor of Massey’s 3.25% Convertible Notes, with aggregate principal outstanding at June 1, 2011 of $659,063. The 3.25% Convertible Notes bear interest at a rate of 3.25% per annum, payable semi-annually in arrears on August 1 and February 1 of each year. The 3.25% Convertible Notes will mature on August 1, 2015, unless earlier repurchased by the Company or converted. The 3.25% Convertible Notes had a fair value of $730,900 at the acquisition date. The Company accounts for the 3.25% Convertible Notes under ASC 470-20, which requires issuers of convertible debt instruments that may be settled wholly or partially in cash upon conversion to separately account for the liability and equity components in a manner reflective of the issuers’ nonconvertible debt borrowing rate. As of December 31, 2014, the carrying amount of the debt was $108,225, net of debt discount of $976. As of December 31, 2013, the carrying amount of the debt was $125,142, net of debt discount of $3,040. As of December 31, 2014 and 2013, the carrying amount of the equity component totaled $110,375. The debt discount is being accreted over the four-year term of the 3.25% Convertible Notes, and provides for an effective interest rate of 4.21%.
The 3.25% Convertible Notes are senior unsecured obligations and rank equally with all of the Company’s existing and future senior unsecured indebtedness. The 3.25% Convertible Notes are guaranteed on a senior unsecured basis by Massey’s subsidiaries (which are among the Company’s subsidiaries), other than certain minor subsidiaries of Massey. The 3.25% Convertible Notes are effectively subordinated to all of the Company’s existing and future secured indebtedness and all existing and future liabilities of the Company’s non-guarantor subsidiaries, including trade payables. The 3.25% Convertible Notes are convertible in certain circumstances and beginning on February 1, 2015 at a conversion rate, subject to adjustment, of the value of 11.4560 shares of common stock per $1,000 principal amount of 3.25% Convertible Notes. From and after the effective date of the Massey Acquisition, the consideration deliverable upon conversion of the 3.25% Convertible Notes ceased to be based upon Massey common stock and instead became based upon Reference Property (as defined in the indenture governing the 3.25% Convertible Notes, (the “3.25% Convertible Notes Indenture”)) consisting of 1.025 shares of Alpha common stock (subject to adjustment upon the occurrence of certain events set forth in the 3.25% Convertible Notes Indenture) plus $10.00 in cash per share of Massey common stock. Upon conversion of the 3.25% Convertible Notes, holders will receive cash up to the principal amount of the notes being converted, and any excess conversion value will be delivered in cash, Reference Property, or a combination thereof, at the Company’s election.
The 3.25% Convertible Notes Indenture contains customary terms and covenants, including that upon certain events of default occurring and continuing, either the trustee or the holders of at least 25% in aggregate principal amount of the 3.25% Convertible Notes then outstanding may declare the principal of the 3.25% Convertible Notes and any accrued and unpaid interest immediately due and payable. In the case of certain events of bankruptcy, insolvency or reorganization relating to the Company, the principal amount of the 3.25% Convertible Notes together with any accrued and unpaid interest thereon will automatically become due and immediately payable.
The 3.25% Convertible Notes were not convertible as of December 31, 2014 or 2013 and are classified as short-term debt as of December 31, 2014.
2.375% Convertible Senior Notes Due April 15, 2015
As of December 31, 2014 and 2013, the Company had $44,458 and $65,889 aggregate principal amount of 2.375% convertible senior notes due April 15, 2015. The 2.375% Convertible Notes bear interest at a rate of 2.375% per annum, payable semi-annually in arrears on April 15 and October 15 of each year, and will mature on April 15, 2015, unless previously repurchased by the Company or converted. The Company separately accounts for the liability and equity components of its 2.375% Convertible Notes under ASC 470-20, which requires issuers of convertible debt instruments that may be settled wholly or partially in cash upon conversion to separately account for the liability and equity components in a manner reflective of the issuers’ nonconvertible debt borrowing rate. The related deferred loan costs and discount are being amortized and accreted, respectively, over the seven-year term of the 2.375% Convertible Notes, and provide for an effective interest rate of 8.64%. As of December 31, 2014 and 2013, the carrying amounts of the debt component were $43,503 and $60,647, respectively. As of December 31, 2014 and 2013, the unamortized debt discount was $955 and $5,242, respectively. As of December 31, 2014 and 2013, the carrying amount of the equity component was $69,851.
The 2.375% Convertible Notes are the Company’s senior unsecured obligations and rank equally with all of the Company’s existing and future senior unsecured indebtedness. The 2.375% Convertible Notes are effectively subordinated to all of the Company’s existing and future secured indebtedness and all existing and future liabilities of the Company’s subsidiaries, including trade payables. The 2.375% Convertible Notes are convertible in certain circumstances and beginning on January 15, 2015 at an initial conversion rate of 18.2962 shares of common stock per one thousand principal amount of 2.375% Convertible Notes, subject to adjustment upon the occurrence of certain events set forth in the indenture governing the 2.375% Convertible Notes (the “2.375% Convertible Notes Indenture”). Upon conversion of the 2.375% Convertible Notes, holders will receive cash up to the principal amount of the notes to be converted, and any excess conversion value will be delivered in cash, shares of common stock or a combination thereof, at the Company’s election.
The 2.375% Convertible Notes Indenture contains customary terms and covenants, including that upon certain events of default occurring and continuing, either the trustee, Union Bank of California, or the holders of not less than 25% in aggregate principal amount of the 2.375% Convertible Notes then outstanding may declare the principal of 2.375% Convertible Notes and any accrued and unpaid interest thereon immediately due and payable. In the case of certain events of bankruptcy, insolvency or reorganization relating to the Company, the principal amount of the 2.375% Convertible Notes together with any accrued and unpaid interest thereon will automatically become due and be immediately payable.
The 2.375% Convertible Notes were not convertible as of December 31, 2014 and 2013 and are classified as short-term debt as of December 31, 2014.
Repurchases of 2.375% and 3.25% Convertible Senior Notes due 2015
During the year ended December 31, 2014, the Company completed the repurchase of approximately $21,431 of its outstanding 2.375% Convertible Notes and approximately $18,981 of its outstanding 3.25% Convertible Notes, each of which are due in 2015, and recorded a loss on early extinguishment of debt of $2,022. During the year ended 2013, the Company repurchased approximately $3,400 of its outstanding 2.375% Convertible Notes and approximately $5,100 of its outstanding 3.25% Convertible Notes and recorded a gain on early extinguishment of debt of $158. On October 25, 2012, the Company completed a cash tender offer for a portion of the outstanding 3.25% Convertible Notes. The Company paid $115,943 to redeem $122,511 of the 3.25% Convertible Notes. The Company recognized a gain on early extinguishment of debt of $773.
Capital Leases
The Company entered into capital leases for certain property and other equipment during 2014 and 2013. The Company’s liability for capital leases as of December 31, 2014 and 2013 totaled $51,362 and $58,874, respectively.
Future Maturities
Future maturities of long-term debt as of December 31, 2014 are as follows:
2015	$	180,177
2016	15,887
2017	363,065
2018	506,676
2019	806,574
Thereafter	2,146,686
Total long-term debt	$	4,019,065

Asset_Retirement_Obligations

Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation [Abstract]
Asset Retirement Obligations	Asset Retirement Obligations
	As of December 31, 2014 and 2013, the Company had recorded asset retirement obligation accruals for mine reclamation and closure costs totaling $640,501 and $799,426, respectively. The portion of the costs expected to be paid within a year of $102,493 and $70,851, as of December 31, 2014 and 2013, respectively, is included in accrued expenses and other current liabilities. There were no assets that were legally restricted for purposes of settling asset retirement obligations at December 31, 2014 or 2013. The Company is self-bonded for certain of its asset retirement obligations in West Virginia and Wyoming, subject to periodic evaluation of the Company’s financial position by the applicable state and meeting certain financial ratios defined by each state. Asset retirement obligations for states other than Wyoming and West Virginia are secured by surety bonds.
	Changes in the asset retirement obligations were as follows:
	Total asset retirement obligations at December 31, 2012	$	856,701
	Accretion for the period	60,274
	Sites added during the period	1,667
	Revisions in estimated cash flows (1)	(74,354		)
	Expenditures for the period	(44,862		)
	Total asset retirement obligations at December 31, 2013	799,426
	Accretion for the period	47,698
	Sites added during the period	2,685
	Revisions in estimated cash flows (1) (2)	(133,680		)
	Asset sales	(20,108		)
	Expenditures for the period	(55,520		)
	Total asset retirement obligations at December 31, 2014	$	640,501
	Less current portion	(102,493		)
	Long-term portion	$	538,008
	(1)	Amount includes $107,263 and $66,521, primarily related to changes in the discount rate, which were recorded as a reduction to cost of coal sales in the Consolidated Statements of Operations for the years ended December 31, 2014 and 2013, respectively.
	(2)	During the fourth quarter of 2014, the Company discovered a programming logic error in the system used to calculate its asset retirement obligations. The faulty logic caused liability amounts for certain permits in certain circumstances to be miscalculated and the asset retirement obligations related to these permits were overstated in 2013 and 2012. The programming logic was corrected and the Company determined that the errors were immaterial to the Company's financial statements in 2013 and 2012, and therefore, were corrected in the fourth quarter of 2014. The Company corrected these errors by decreasing its asset retirement obligations by $51,361, cost of coal sales by $29,987 and depreciation, depletion and amortization by $13,583 for the year ended December 31, 2014. This resulted in a decrease of $43,570 to loss from operations and net loss for the year ended December 31, 2014.

Other_Noncurrent_Liabilities

Other Non-current Liabilities	12 Months Ended
	Dec. 31, 2014
Other Liabilities, Noncurrent [Abstract]
Other Non-current Liabilities	Other Non-current Liabilities
	Other non-current liabilities consisted of the following:
		December 31,
		2014		2013
	Self insured workers’ compensation obligations	$	137,824	$	142,537
	Black lung obligations	144,894		136,457
	Below-market and other contract-related obligations, net (1)	109,908		95,885
	Deferred coal revenue	23,021		33,138
	Other	56,173		57,875
	Total other non-current liabilities	$	471,820	$	465,892
	-1	During the year ended December 31, 2013, the Company recorded a credit of ($55,454) to other expense for the settlement of a contract-related matter.

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments and Fair Value Measurements	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments and Fair Value Measurements	Fair Value of Financial Instruments and Fair Value Measurements
	The estimated fair values of financial instruments are determined based on relevant market information. These estimates involve uncertainty and cannot be determined with precision.
	The carrying amounts for cash and cash equivalents, trade accounts receivable, net, prepaid expenses and other current assets, trade accounts payable, and accrued expenses and other current liabilities approximate fair value due to the short maturity of these instruments.
	The following tables set forth by level, within the fair value hierarchy, the Company’s long-term debt at fair value as of December 31, 2014 and 2013, respectively:
		December 31, 2014
		Carrying			Total Fair		Quoted Prices			Significant		Significant
		Amount			Value		in Active			Other		Unobservable
							Markets			Observable		Inputs
							(Level 1)			Inputs		(Level 3)
										(Level 2)
	6.25% senior notes due 2021	$	700,000		$	208,950	$	208,950		$	—	$	—
	7.50% senior secured second lien notes due 2020	500,000			320,000		320,000			—		—
	6.00% senior notes due 2019	800,000			240,000		240,000			—		—
	9.75% senior notes due 2018 (1)	497,779			233,430		233,430			—		—
	Term loan due 2020 (2)	611,655			499,424		—			499,424		—
	4.875% convertible senior notes due 2020 (3)	272,886			125,494		125,494			—		—
	3.75% convertible senior notes due 2017 (4)	302,378			172,500		172,500			—		—
	3.25% convertible senior notes due 2015 (5)	108,225			104,014		104,014			—		—
	2.375% convertible senior notes due 2015 (6)	43,503			43,368		43,368			—		—
	Total long-term debt	$	3,836,426		$	1,947,180	$	1,447,756		$	499,424	$	—
		December 31, 2013
		Carrying			Total Fair		Quoted Prices			Significant		Significant
		Amount			Value		in Active			Other		Unobservable
							Markets			Observable		Inputs
							(Level 1)			Inputs		(Level 3)
										(Level 2)
	6.25% senior notes due 2021	$	700,000		$	602,000	$	602,000		$	—	$	—
	6.00% senior notes due 2019	800,000			694,872		694,872			—		—
	9.75% senior notes due 2018 (1)	496,547			560,250		560,250			—		—
	Term loan due 2020 (2)	617,460			617,291		—			617,291		—
	4.875% convertible senior notes due 2020 (3)	264,283			372,606		372,606			—		—
	3.75% convertible senior notes due 2017 (4)	290,219			360,956		360,956			—		—
	3.25% convertible senior notes due 2015 (5)	125,142			126,904		126,904			—		—
	2.375% convertible senior notes due 2015 (6)	60,647			65,882		65,882			—		—
	Total long-term debt	$	3,354,298		$	3,400,761	$	2,783,470		$	617,291	$	—
	(1)	Net of debt discount of $2,221 and $3,453 as of December 31, 2014 and 2013, respectively.
	(2)	Net of debt discount of $2,407 and $2,853 as of December 31, 2014 and 2013, respectively.
	(3)	Net of debt discount of $72,114 and $80,717 as of December 31, 2014 and 2013, respectively.
	(4)	Net of debt discount of $42,622 and $54,781 as of December 31, 2014 and 2013, respectively.
	(5)	Net of debt discount of $976 and $3,040 as of December 31, 2014 and 2013, respectively.
	(6)	Net of debt discount of $955 and $5,242 as of December 31, 2014 and 2013, respectively.
	The following tables set forth by level, within the fair value hierarchy, the Company’s financial and non-financial assets and liabilities that were accounted for at fair value on a recurring basis as of December 31, 2014 and 2013, respectively. Financial and non-financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the determination of fair value for assets and liabilities and their placement within the fair value hierarchy levels.
		December 31, 2014
		Total Fair			Quoted Prices		Significant Other			Significant
		Value			in Active		Observable			Unobservable
					Markets		Inputs			Inputs
					(Level 1)		(Level 2)			(Level 3)
	Financial assets (liabilities):
	U.S. treasury and agency securities	$	80,093		$	80,093	$	—		$	—
	Mutual funds held in rabbi trust	$	10,107		$	10,107	$	—		$	—
	Corporate equity securities	$	126,820		$	126,820	$	—		$	—
	Corporate debt securities	$	325,076		$	—	$	325,076		$	—
	Forward coal sales	$	760		$	—	$	760		$	—
	Commodity swaps	$	(23,614	)	$	—	$	(23,614	)	$	—
		December 31, 2013
		Total Fair			Quoted Prices		Significant Other			Significant
		Value			in Active		Observable			Unobservable
					Markets		Inputs			Inputs
					(Level 1)		(Level 2)			(Level 3)
	Financial assets (liabilities):
	U.S. treasury and agency securities	$	81,497		$	81,497	$	—		$	—
	Mutual funds held in rabbi trust	$	9,330		$	9,330	$	—		$	—
	Corporate debt securities	$	255,572		$	—	$	255,572		$	—
	Forward coal sales	$	(398	)	$	—	$	(398	)	$	—
Commodity swaps	$	10,403		$	—	$	10,403		$	—
The following methods and assumptions were used to estimate the fair values of the assets and liabilities in the tables above.
Level 1 Fair Value Measurements
U.S. Treasury and Agency Securities, Corporate Equity Securities and Mutual Funds Held in Rabbi Trust — The fair value is based on observable market data.
6.25% senior notes due 2021, 7.50% senior secured second lien notes due 2020, 6.00% senior notes due 2019, 9.75% senior notes due 2018 (collectively, the “Senior Notes”), 4.875% Convertible Notes, 3.75% Convertible Notes, 2.375% Convertible Notes, and 3.25% Convertible Notes (collectively, the “Convertible Notes”) - The fair value is based on observable market data.
Level 2 Fair Value Measurements
Corporate Debt Securities — The fair values of the Company’s corporate debt securities are obtained from a third-party pricing service provider. The fair values provided by the pricing service provider are estimated using pricing models, where the inputs to those models are based on observable market inputs including credit spreads and broker-dealer quotes, among other inputs. The Company classifies the prices obtained from the pricing services within Level 2 of the fair value hierarchy because the underlying inputs are directly observable from active markets, however, the pricing models used entail a certain amount of subjectivity and therefore differing judgments in how the underlying inputs are modeled which could result in different estimates of fair value.
Forward Coal Sales — The fair values of the forward coal sale contracts were estimated using discounted cash flow calculations based upon actual contract prices and forward commodity price curves. The curves were obtained from independent pricing services reflecting broker market quotes. The fair values are adjusted for counter-party credit risk, when applicable.
Commodity Swaps — The fair values of commodity swaps are estimated using valuation models which include assumptions about commodity prices based on those observed in the underlying markets. The fair values are adjusted for counter-party credit risk.
Term Loan due 2020 — The fair value of the term loan due 2020 is estimated based on market rates of interest offered for debt of similar maturities.

Derivative_Financial_Instrumen

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedges, Assets [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments
	Forward Contracts
	The Company manages price risk for coal sales and purchases through the use of coal supply agreements. The Company evaluates each of its coal sales and coal purchase forward contracts to determine whether they meet the definition of a derivative and if so, whether they qualify for the normal purchase normal sale (“NPNS”) exception. For those contracts that do meet the definition of a derivative, certain contracts also qualify for the NPNS exception based on management’s intent and ability to physically deliver or take physical delivery of the coal. Contracts that meet the definition of a derivative and do not qualify for the NPNS exception are accounted for at fair value and, accordingly, the Company includes the unrealized gains and losses in current period earnings or losses.
	Swap Agreements
	Commodity Swaps
	The Company uses diesel fuel in its production process and incurs significant expenses for its purchases. Diesel fuel expenses represented approximately 6% of cost of coal sales for the years ended December 31, 2014, 2013, and 2012, respectively. The Company is subject to the risk of price volatility for this commodity and as a part of its risk management strategy, the Company has entered into swap agreements with financial institutions to mitigate the risk of price volatility for diesel fuel. The terms of the swap agreements allow the Company to pay a fixed price and receive a floating price, which provides a fixed price per unit for the volume of purchases being hedged. As of December 31, 2014, the Company had swap agreements outstanding to hedge the variable cash flows related to 43% and 5% of anticipated diesel fuel usage for calendar years 2015 and 2016, respectively. The average fixed price for these diesel fuel swaps is $2.76 per gallon and $2.74 per gallon for calendar years 2015 and 2016, respectively. All cash flows associated with derivative instruments are classified as operating cash flows in the Consolidated Statements of Cash Flows for the years ended December 31, 2014, 2013, and 2012.
	The following tables present the fair values and location of the Company’s derivative instruments within the Consolidated Balance Sheets:
				Asset Derivatives
	Derivatives not designated as	Statement of Financial Position Location		December 31,			December 31,
	cash flow hedging instruments			2014			2013
	Commodity swaps	Prepaid expenses and other current assets		$	429		$	8,898
	Commodity swaps	Other non-current assets		—			1,772
	Forward coal sales	Prepaid expenses and other current assets		760			—
				$	1,189		$	10,670
				Liability Derivatives
	Derivatives not designated as	Statement of Financial Position Location		December 31,			December 31,
	cash flow hedging instruments			2014			2013
	Commodity swaps	Other non-current liabilities		$	3,022		$	31
	Commodity swaps	Accrued expenses and other current liabilities		21,021			236
	Forward coal sales	Accrued expenses and other current liabilities		—			398
				$	24,043		$	665
	The following tables present the gains and losses from derivative instruments for the years ended December 31, 2014, 2013, and 2012 and their location within the Consolidated Financial Statements:
			Gain (loss) reclassified from accumulated other									Gain (loss) recorded in accumulated other comprehensive income (loss)
			comprehensive income (loss) to earnings
	Derivatives designated as		2014			2013			2012			2014		2013			2012
	cash flow hedging instruments
	Commodity swaps (1) (3)		$	2,341		$	1,911		$	10,390		$	—	$	(908	)	$	13,831
	Commodity options (2) (3)		—			(68		)	—			—		(63		)	(19		)
			$	2,341		$	1,843		$	10,390		$	—	$	(971	)	$	13,812
	(1)	For the twelve months ended December 31, 2014, amounts included in cost of coal sales and coal revenues in the Consolidated Statements of Operations. For the twelve months ended December 31, 2013 and 2012, amounts included in cost of coal sales, other revenues and coal revenues in the Consolidated Statements of Operations.
	(2)	Amounts are recorded in other revenues in the Consolidated Statements of Operations.
	(3)	Net of tax.
			Gain (loss) recorded in earnings
	Derivatives not designated as		2014			2013			2012
	cash flow hedging instruments
	Forward coal sales (1)		$	1,158		$	(15,756	)	$	(11,887	)
	Forward coal purchases (1)		—			4			15,452
	Commodity swaps (2)		(26,910		)	9,539			348
	Commodity options-coal (1)		—			—			17
	Interest rate swaps (3)		—			—			(400		)
	Total		$	(25,752	)	$	(6,213	)	$	3,530
	(1)	Amounts are recorded as a component of other revenues in the Consolidated Statements of Operations.
	(2)	Amounts are recorded as a component of coal revenues, cost of coal sales and other expenses in the Consolidated Statements of Operations.
	(3)	Amount is recorded as a component of interest expense in the Consolidated Statements of Operations.
	Unrealized gains and losses recorded in accumulated other comprehensive income (loss) are reclassified to income or loss as the financial swaps settle and the Company purchases the underlying items that are being hedged. During the next twelve months, the Company expects to reclassify approximately $509, net of tax, to earnings.
	During the third quarter of 2013, the Company elected to cease applying hedge accounting to outstanding commodity swaps. Changes in fair value of those derivative instruments are now recorded in earnings. Amounts previously recognized in accumulated other comprehensive income (loss) will be recognized in income when the underlying transactions are consummated.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes
	Significant components of income tax expense (benefit) were as follows:
		Years Ended December 31,
		2014			2013			2012
	Current tax (benefit) expense:
	Federal	$	(15,430	)	$	(3,949	)	$	(1,686	)
	State	616			(240		)	6,265
		$	(14,814	)	$	(4,189	)	$	4,579
	Deferred tax benefit:
	Federal	$	(24,886	)	$	(203,560	)	$	(482,015	)
	State	(15,591		)	(8,801		)	(72,560		)
		$	(40,477	)	$	(212,361	)	$	(554,575	)
	Total income tax benefit:
	Federal	$	(40,316	)	$	(207,509	)	$	(483,701	)
	State	(14,975		)	(9,041		)	(66,295		)
		$	(55,291	)	$	(216,550	)	$	(549,996	)
	A reconciliation of the statutory federal income tax benefit at 35% to the actual income tax benefit is as follows:
		Years Ended December 31,
		2014			2013			2012
	Federal statutory income tax benefit	$	(325,588	)	$	(465,517	)	$	(1,045,500	)
	Increases (reductions) in taxes due to:
	Percentage depletion allowance	(28,630		)	(34,702		)	(76,252		)
	State taxes, net of federal tax impact	(2,891		)	(49,523		)	(25,748		)
	State tax rate and NOL change, net of federal tax benefit	—			(2,524		)	(8,180		)
	Change in valuation allowances	196,646			207,681			43,885
	Non-deductible stock-based compensation	6,627			5,509			—
	Non-deductible fines and penalties	2,349			14,513			3,996
	State apportionment change, net of federal tax impact	(5,811		)	15,425			(18,654		)
	Non-deductible goodwill impairment	108,028			88,586			572,503
	Reversal of reserves for uncertain tax positions	(8,090		)	—			—
	Other, net	2,069			4,002			3,954
	Income tax benefit	$	(55,291	)	$	(216,550	)	$	(549,996	)
	Deferred income taxes result from temporary differences between the reporting of amounts for financial statement purposes and income tax purposes. The net deferred tax assets and liabilities included in the Consolidated Balance Sheets include the following amounts:
		December 31,
		2014			2013
	Deferred tax assets:
	Asset retirement obligations	$	236,389		$	297,405
	Reserves and accruals not currently deductible	80,492			145,870
	Pension and postretirement medical obligations	460,252			374,662
	Alternative minimum tax credit carryforwards	208,759			210,742
	Goodwill	28,060			31,700
	Workers’ compensation obligations	107,557			104,424
	Acquired intangibles, net	15,870			6,469
	Deferred revenue	19,095			28,080
	Other	47,541			36,101
	Net operating loss carryforwards	1,002,863			797,284
	Gross deferred tax assets	2,206,878			2,032,737
	Less valuation allowance	(563,142		)	(294,073		)
	Total net deferred tax assets	1,643,736			1,738,664
	Deferred tax liabilities:
	Property, equipment and mineral reserves	(2,218,426		)	(2,367,180		)
	Debt discount	(43,059		)	(53,490		)
	Prepaid expenses	(43,822		)	(57,411		)
	Equity and cost method investments and marketable securities	(48,715		)	(31,177		)
	Other	(8,729		)	(12,201		)
	Total deferred tax liabilities	(2,362,751		)	(2,521,459		)
	Net deferred tax liability	$	(719,015	)	$	(782,795	)
	The breakdown of the net deferred tax liability as recorded in the accompanying Consolidated Balance Sheets is as follows:
		December 31,
		2014			2013
	Current asset	$	54,451		$	118,757
	Noncurrent liability	(773,466		)	(901,552		)
	Total net deferred tax liability	$	(719,015	)	$	(782,795	)
	Changes in the valuation allowance during the years ended December 31, 2014, 2013 and 2012 were as follows:
	December 31,
	2014			2013			2012
Valuation allowance beginning of period	$	294,073		$	86,392		$	41,940
Increase in valuation allowance not affecting income tax expense	72,423			—			567
Increase in valuation allowance recorded as an increase to income tax expense	196,646			207,681			43,885
Valuation allowance end of period	$	563,142		$	294,073		$	86,392
The Company recorded an increase of $269,069 to its deferred tax asset valuation allowance during the year ended December 31, 2014, of which $196,646 was recorded to continuing operations and $72,423 was recorded to other comprehensive income. The portion of the valuation allowance recorded to other comprehensive income is the result of an increase in deferred tax assets recorded in other comprehensive income primarily related to remeasurement of employee benefit plan liabilities.
The change in valuation allowance results from an increase in net operating losses and other deferred tax assets for which the Company is unable to support realization. The Company currently is relying primarily on the reversal of taxable temporary differences, along with consideration of taxable income via carryback to prior years, and tax planning strategies to support the realization of deferred tax assets. The Company assesses the realizability of its deferred tax assets including scheduling the reversal of its deferred tax liabilities to determine the amount of valuation allowance needed. Scheduling the reversal of deferred tax asset and liability balances requires judgment and estimation. The Company believes the deferred tax liabilities relied upon as future taxable income in its assessment will reverse in the same period and jurisdiction and are of the same character as the temporary differences giving rise to the deferred tax assets that will be realized. The valuation allowance recorded represents the portion of deferred tax assets for which the Company is unable to support realization through the methods described above. The Company has concluded that it is more likely than not that the remaining deferred tax assets, net of valuation allowances, are realizable.
At December 31, 2014, the Company has regular tax net operating loss carryforwards for Federal income tax purposes of $2,598,751 which are available to offset regular Federal taxable income. The Federal net operating losses generated will expire between years 2023 and 2034. A valuation allowance has been provided for $1,296,142 of the federal net operating losses. The Company has gross net operating loss carryforwards for state income taxes of $2,377,111 which will expire between years 2015 and 2034. A valuation allowance has been provided for $1,893,860 of the state net operating losses. The Company also has alternative minimum tax credit carryforwards of $208,759, which are available to reduce federal regular income tax in excess of the alternative minimum tax, if any, over an indefinite period.
The total amount of unrecognized tax benefits that would affect the Company’s effective tax rate if recognized is $2,721 as of December 31, 2014. The Company believes that it is reasonably possible that a decrease in unrecognized tax benefits of $2,721 may be necessary during the next twelve months, as a result of settlements with taxing authorities.
The Company’s policy is to classify interest and penalties related to uncertain tax positions as part of income tax expense. As of December 31, 2014, the Company has recorded accrued interest and penalties of $313 and $514, respectively.
The following reconciliation illustrates the Company’s liability for uncertain tax positions:
	December 31,
	2014			2013			2012
Unrecognized tax benefits — beginning of period	$	28,741		$	28,741		$	28,741
Reduction as a result of settlement with taxing authorities	(26,020		)	—			—
Unrecognized tax benefits - end of period	$	2,721		$	28,741		$	28,741
Tax years 2011-2014 remain open to federal and state examination. The Internal Revenue Service initiated a corporate income tax audit during the second quarter of 2011 for the Company’s 2008 and 2009 tax years and during the second quarter of 2012 for the Company’s 2010 tax year. The 2009 and 2010 audits were settled during the second quarter of 2014. As a result, the Company determined that particular uncertain tax positions were deemed to be effectively settled, resulting in a decrease in unrecognized tax benefits of $26,020 and the recording of an income tax benefit of $8,090. The settlement of the 2009 and 2010 audits resulted in no material impact on cash paid for income taxes. The 2008 audit was settled during the third quarter of 2012 with no material effect on the Consolidated Financial Statements.

Employee_Benefit_Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2014
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Employee Benefit Plans	Employee Benefit Plans
	The Company provides several types of benefits for its employees, including postemployment health care and life insurance, defined benefit and defined contribution pension plans, and workers’ compensation and black lung benefits.
	In March 2010, the Patient Protection and Affordable Care Act (“PPACA”) was enacted, potentially impacting the costs to provide healthcare benefits to the Company’s eligible active and certain retired employees and workers’ compensation benefits related to occupational disease resulting from coal workers’ pneumoconiosis (“Black Lung”). The PPACA has both short-term and long-term implications on healthcare benefit plan standards. Implementation of this legislation is planned to occur in phases, with multiple changes already having taken effect, and with additional changes extending over the next several years through 2018 and beyond. Plan standard changes that affect the Company in the short term include minimum essential coverage requirements, restrictions on the plan cost contribution level an employer may require of its employees, the establishment of state and federal exchanges designed to compete with private insurers, a mandate that all individuals purchase health insurance (or pay a penalty), and a requirement that all employers with at least 50 full-time employees provide health insurance to their respective workforces (or pay a penalty). Plan standard changes that are expected to affect the Company in the long term include an excise tax on “high cost” plans and the elimination of annual dollar limits per covered individual, among other standard requirements.
	Beginning in 2018, the PPACA will impose a 40% excise tax on employers to the extent that the value of their healthcare plan coverage exceeds certain dollar thresholds. The Company has accrued $36,599 as of December 31, 2014 for the estimated impact of the PPACA, which is included in the liability for postretirement medical benefit obligations. The Company anticipates that certain government agencies will provide additional regulations or interpretations concerning the application of this excise tax. The Company will need to continue to evaluate the impact of the PPACA in future periods, and when these regulations or interpretations are published, the Company will evaluate its assumptions in light of the new information.
	The PPACA also amended previous legislation related to coal workers’ Black Lung, providing automatic extension of awarded lifetime benefits to surviving spouses and providing changes to the legal criteria used to assess and award claims.
	(a) Company Administered Postretirement Health Care and Life Insurance Benefits
	The Company provides postretirement medical and life insurance benefits to certain eligible employees under various plans. Certain plans are contributory while others are noncontributory. Additionally, certain plans are established by collective bargaining agreements. To be eligible, retirees must meet certain age and service requirements. Depending on year of retirement, benefits may be subject to annual deductibles, coinsurance requirements, lifetime limits and retiree contributions. These plans are unfunded. Beginning January 1, 2013, the majority of the Company’s post-65 union retirees were enrolled in an Employer Group Waiver Plan (“EGWP”), and the majority of the Company’s post-65 non-union retirees were moved to a health reimbursement account (“HRA”) arrangement. Beginning January 1, 2015, the remainder of the Company's non-union eligible participants will receive benefits through an HRA arrangement. The Company will provide a fixed annual notional credit through the HRA to most retirees under this arrangement, which retirees may use to purchase insurance through a Medicare exchange.
	The components of the change in accumulated benefit obligations of the plans for postretirement medical benefits were as follows:
		December 31,
		2014				2013
	Change in benefit obligations:
	Accumulated benefit obligation-beginning period:	$	942,693			$	1,006,193
	Service cost	11,145				13,785
	Interest cost	42,018				40,170
	Actuarial loss (gain)	129,270				(84,769		)
	Benefits paid	(34,977		)		(32,686		)
	Change in plan provisions	(26,196		)		—
	Accumulated benefit obligation-end of period	$	1,063,953			$	942,693
	Change in fair value of plan assets:
	Employer contributions	$	34,977			$	32,686
	Benefits paid	(34,977		)		(32,686		)
	Fair value of plan assets at December 31	—				—
	Funded status	$	(1,063,953	)		$	(942,693	)
	Amounts recognized in the consolidated balance sheets:
	Current liabilities	$	(46,678	)		$	(46,678	)
	Long-term liabilities	(1,017,275		)		(896,015		)
		$	(1,063,953	)		$	(942,693	)
	Amounts recognized in accumulated other comprehensive (income) loss:
	Prior service credit	$	(48,048	)		$	(24,521	)
	Net actuarial loss	193,559				64,288
		$	145,511			$	39,767
	The following table details the components of the net periodic benefit cost for postretirement medical benefits:
		Years Ended December 31,
		2014				2013			2012
	Service cost	$	11,145			$	13,785		$	16,408
	Interest cost	42,018				40,170			42,122
	Amortization of net actuarial loss	—				2,872			4,656
	Amortization of prior service credit	(4,477		)		(3,819		)	(641		)
	Net periodic benefit cost	$	48,686			$	53,008		$	62,545
	Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss are as follows:
		Years Ended December 31,
		2014				2013			2012
	Current year actuarial loss (gain)	$	129,270			$	(84,769	)	$	(47,753	)
	Prior service credit for period	(28,003		)		—			(44,835		)
	Amortization of net actuarial (loss)	—				(2,872		)	(4,656		)
	Amortization of prior service credit	4,477				3,819			641
	Total recognized in other comprehensive loss (income)	$	105,744			$	(83,822	)	$	(96,603	)
	Total recognized in net periodic benefit cost and other comprehensive loss (income)	$	154,429			$	(30,815	)	$	(34,058	)
	The estimated amount that will be amortized from accumulated other comprehensive (income) loss into net period benefit cost in 2015 is as follows:
	Prior service credit	$	(4,477	)
	The weighted-average assumptions used to determine the postretirement plans’ benefit obligation as of December 31, 2014 and 2013 were as follows:
		December 31,
		2014			2013
	Discount rate	3.93	%		4.68	%
	The weighted average discount rates used in determining net periodic postretirement medical benefit cost for the years ended December 31, 2014, 2013, and 2012 were as follows:
		Years Ended December 31,
		2014		2013		2012
	Discount rate	4.56%		4.18%		4.10%
	The discount rate assumption is determined from a published yield-curve table matched to timing of the Company’s projected cash out flows.
	The following presents information about the postretirement plans’ weighted-average annual rate of increase in the per capita cost of covered benefits (i.e., health care cost trend rate):
	Health care cost trend rate assumed for the next year	7.5	%
	Rate to which the cost trend is assumed to decline (ultimate trend rate)	5	%
	Year that the rate reaches the ultimate trend rate	2020
	Assumed health care trend rates have a significant effect on the amounts reported for the health care plans. A one-percentage-point change in assumed health care trend rates would have the following effects as of and for the year ended December 31, 2014:
	One Percentage				One Percentage
	Point Increase				Point Decrease
Effect on total service and interest cost components	$	8,250			$	(6,646	)
Effect on accumulated postretirement benefit obligation	$	157,163			$	(126,240	)
The following represents the Company’s expected future postretirement medical and life insurance benefit payments for the next ten years, which reflect expected future service, as appropriate:
	Postretirement
	Medical and
	Life Insurance
	Benefits
2015	$	46,076
2016	51,233
2017	53,748
2018	55,574
2019	56,381
2019-2023	274,273
	$	537,285
(b) Company Administered Defined Benefit Pension Plans
The Company has three qualified non-contributory defined benefit pension plans, which cover certain salaried and non-union hourly employees. Participants accrued benefits either based on certain formulas, the participant’s compensation prior to retirement, or plan specified amounts for each year of service with the Company. Benefits are frozen under these plans.
In addition to the qualified defined benefit plans noted above, the Company also has a nonqualified restoration plan for certain salaried employees. Participants in this nonqualified plan accrued benefits based on the qualified plan formula, however, where the benefit or pensionable earnings were capped by the Internal Revenue Service (“IRS”) limitations, this nonqualified plan restores benefits in excess of the IRS limits. The Company also has a non-qualified Supplemental Executive Retirement Plan (“SERP”). Benefits are based on the employee’s compensation prior to retirement or the plan becoming frozen. Benefits are frozen under these plans and they are unfunded.
The qualified non-contributory defined benefit pension plans are collectively referred to as the “Pension Plans”. The non-qualified supplement benefit pension plans and the non-qualified Supplement Executive Retirement Plan are collectively referred to as the “SERPs”.
Annual funding contributions to the Pension Plans are made as recommended by consulting actuaries based upon the ERISA funding standards. Plan assets consist of equity and fixed income funds, private equity funds and a guaranteed insurance contract.
The following tables set forth the plans’ accumulated benefit obligations, fair value of plan assets and funded status:
	December 31,
	2014				2013
Change in benefit obligation:
Accumulated benefit obligation at beginning of period	$	629,379			$	792,383
Interest cost	31,210				29,497
Actuarial loss (gain)	145,609				(135,832		)
Benefits paid	(24,311		)		(23,607		)
Settlements	(13,142		)		(33,062		)
Accumulated benefit obligation at end of period	$	768,745			$	629,379
Change in fair value of plan assets:
Fair value of plan assets at beginning of period	$	535,270			$	561,151
Actual return on plan assets	44,420				27,786
Employer contributions	6,797				3,002
Benefits paid	(24,311		)		(23,607		)
Settlements	(13,142		)		(33,062		)
Fair value of plan assets at end of period	549,034				535,270
Funded status	(219,711		)		(94,109		)
Accrued benefit cost at end of year	$	(219,711	)		$	(94,109	)
Gross amounts recognized in accumulated other comprehensive (income) loss were as follows:
	Years Ended December 31,
	2014				2013
Net actuarial loss	$	146,866			$	12,631
The following table details the components of net periodic benefit credit:
	Years Ended December 31,
	2014				2013			2012
Service cost	$	—			$	—		$	—
Interest cost	31,210				29,497			31,990
Expected return on plan assets	(35,207		)		(36,199		)	(38,798		)
Amortization of net actuarial loss	10				822			1,837
Settlement loss (gain)	2,151				(212		)	1,207
Total	$	(1,836	)		$	(6,092	)	$	(3,764	)
Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss are as follows:
	Years Ended December 31,
	2014				2013			2012
Current year actuarial loss (gain)	$	136,396			$	(127,419	)	$	67,042
Amortization of net actuarial loss	(10		)		(822		)	(1,837		)
Settlement (loss) gain	(2,151		)		212			(1,207		)
Total recognized in other comprehensive loss (income)	$	134,235			$	(128,029	)	$	63,998
Total recognized in net periodic benefit cost and other comprehensive loss (income)	$	132,399			$	(134,121	)	$	60,234
No amounts are expected to be amortized from accumulated other comprehensive (income) loss into net period benefit cost in 2015.
The following table presents information applicable to plans with accumulated benefit obligations in excess of plan assets:
	December 31,
	2014				2013
Projected benefit obligation	$	768,745			$	629,379
Accumulated benefit obligation	$	768,745			$	629,379
Fair value of plan assets	$	549,034			$	535,270
The current portion of the Company’s Pension Plans liability is the amount by which the actuarial present value of benefits included in the benefit obligation payable in the next twelve months exceeds the fair value of plan assets. However, even though the plan may be underfunded, if there are sufficient plan assets to make expected benefit payments to plan participants in the succeeding twelve months, no current liability is recognized. Accordingly, there was no current pension liability reflected in the Consolidated Balance Sheets as of December 31, 2014 and 2013.
The weighted-average actuarial assumptions used in determining the benefit obligations as of December 31, 2014 and 2013 were as follows:
	December 31,
	2014		2013
Discount rate	4.00%		4.87%
The weighted-average actuarial assumptions used to determine net periodic benefit cost for the years ended December 31, 2014 and 2013 were as follows:
	December 31,
	2014		2013		2012
Discount rate	4.93%		4.21%		4.22%
Rate of increase in future compensation (a)	N/A		N/A		N/A
Expected long-term return on plan assets	6.75%		6.75%		7.25%
Measurement date	December 31, 2014		December 31, 2013		December 31, 2012
(a) These Pension Plans are frozen.
The discount rate assumption is determined from a published yield-curve table matched to timing of the Company’s projected cash out flows.
The expected long-term return on assets of the Pension Plans is established at the beginning of each year by the Company’s Benefits Committee in consultation with the plans’ actuaries and outside investment advisors. This rate is determined by taking into consideration the Pension Plans’ target asset allocation, expected long-term rates of return on each major asset class by reference to long-term historic ranges, inflation assumptions and the expected additional value from active management of the Pension Plans’ assets. For the determination of net periodic benefit cost in 2015, the Company will utilize an expected long-term return on plan assets of 6.50%.
Assets of the Pension Plans are held in trusts and are invested in accordance with investment guidelines that have been established by the Company’s Benefits Committee in consultation with outside investment advisors. The target allocation for 2015 and the actual asset allocation as reported at December 31, 2014 is as follows:
	Target			Percentage of
	Allocation			Plan Assets
	Percentages			2014
	2015
Equity funds	38	%		44	%
Fixed income funds	60	%		54	%
Private equity funds/guaranteed insurance contract	2	%		2	%
Total	100	%		100	%
The asset allocation targets have been set with the expectation that the Pension Plans’ assets will fund the expected liabilities within an appropriate level of risk. In determining the appropriate target asset allocations the Benefits Committee considers the demographics of the Pension Plans’ participants, the funding status of each plan, the Company’s contribution philosophy, the Company’s business and financial profile and other associated risk factors. The Pension Plans’ assets are periodically rebalanced among the major asset categories to maintain the asset allocation within a specified range of the target allocation percentage.
For the years ended December 31, 2014, 2013 and 2012, $6,797, $3,002 and $3,736, respectively, of cash contributions were made to the Pension Plans and SERPs. The Company expects to contribute $2,216 to the Pension Plans in 2015.
The following represents expected future pension benefit and SERP payments for the next ten years:
2015	$	29,530
2016	30,427
2017	31,830
2018	33,004
2019	34,089
2019-2023	182,079
	$	340,959
The fair values of the Company’s Pension Plans’ assets as of December 31, 2014, by asset category are as follows:
					Quoted Market			Significant				Significant
					Prices in Active			Observable				Unobservable
					Market for			Inputs				Inputs
					Identical
					Assets
Asset Category	Total				(Level 1)			(Level 2)				(Level 3)
Equity securities:
Multi-asset fund (a)	$	211,425			$	—		$	211,425			$	—
Fixed income securities:
Bond fund (b)	320,574				—			320,574				—
Other types of investments:
Private equity funds (c)	5,040				—			—				5,040
Guaranteed insurance contract	10,062				—			—				10,062
Total	$	547,101			$	—		$	531,999			$	15,102
Receivable (d)	1,933
Total	$	549,034
(a)	This fund contains equities (domestic and international), real estate, and bonds.
(b)	This fund contains bonds representing a diversity of sectors and maturities. This fund also includes mortgage-backed securities and U.S. Treasuries.
(c)	This category includes several private equity funds that invest primarily in U.S. and European markets.
(d)	Receivable for investments sold at December 31, 2014, which approximates fair value.
The fair values of the Company’s Pension Plans’ assets as of December 31, 2013, by asset category are as follows:
					Quoted Market			Significant				Significant
					Prices in Active			Observable				Unobservable
					Market for			Inputs				Inputs
					Identical
					Assets
Asset Category	Total				(Level 1)			(Level 2)				(Level 3)
Equity securities:
Multi-asset fund (a)	$	238,699			$	—		$	238,699			$	—
Fixed income securities:
Bond fund (b)	280,434				—			280,434				—
Other types of investments:
Private equity funds (c)	5,480				—			—				5,480
Guaranteed insurance contract	9,732				—			—				9,732
Total	$	534,345			$	—		$	519,133			$	15,212
Receivable (d)	925
Total	$	535,270
(a)	This fund contains equities (domestic and international), real estate, and bonds.
(b)	This fund contains bonds representing a diversity of sectors and maturities. This fund also includes mortgage-backed securities and U.S. Treasuries.
(c)	This category includes several private equity funds that invest primarily in U.S. and European markets.
(d)	Receivable for investments sold at December 31, 2013, which approximates fair value.
Changes in level 3 plan assets for the year ended December 31, 2014 were as follows:
		Fair Value Measurements Using Significant
		Unobservable Inputs (Level 3)
		Private				Guaranteed			Total
		Equity				Insurance
		Funds				Contract
Beginning balance, December 31, 2013		$	5,480			$	9,732		$	15,212
Actual return on plan assets:
Relating to assets still held at the reporting date		601				—			601
Relating to assets sold during the period		177				—			177
Purchases, sales, and settlements		(1,218		)		330			(888		)
Ending balance, December 31, 2014		$	5,040			$	10,062		$	15,102
Changes in level 3 plan assets for the year ended December 31, 2013 were as follows:
		Fair Value Measurements Using Significant
		Unobservable Inputs (Level 3)
		Private				Guaranteed			Total
		Equity				Insurance
		Funds				Contract
Beginning balance, December 31, 2012		$	5,608			$	9,600		$	15,208
Actual return on plan assets:
Relating to assets still held at the reporting date		571				—			571
Relating to assets sold during the period		331				—			331
Purchases, sales, and settlements		(1,030		)		132			(898		)
Ending balance, December 31, 2013		$	5,480			$	9,732		$	15,212
The following is a description of the valuation methodologies used for assets measured at fair value:
Level 1 Plan Assets: Assets consist of individual security positions which are easily traded on recognized market exchanges. These securities are priced and traded daily, and therefore the fund is valued daily.
Level 2 Plan Assets: Funds consist of individual security positions which are mostly securities easily traded on recognized market exchanges. These securities are priced and traded daily, and therefore the fund is valued daily.
Level 3 Plan Assets: Assets are valued monthly or quarterly based on the Net Asset Value “NAV” provided by managers of the underlying fund investments. The NAVs provided typically reflect the fair value of each underlying fund investment, including unrealized gains and losses.
(c)    Multi-Employer Pension Plans
Certain of the Company’s subsidiaries are subject to collective bargaining agreements with expiration dates ranging from December 31, 2016 to June 30, 2017 that require them to participate in a UMWA pension plan (the “1974 Plan”). The plan is a multi-employer pension plan administered by a Board of Trustees appointed by the UMWA and the Bituminous Coal Operators’ Association, and the Company is required to make contributions to the plan at rates defined by the various contracts. The 1974 Plan’s legal name is United Mine Workers of America 1974 Pension Plan and the Employer Identification Number is 52-1050282. The 1974 Plan is considered to be in Seriously Endangered Status for the plan year beginning July 1, 2013, because the actuary determined that the 1974 Plan’s funded percentage is less than 80%, and the 1974 Plan is projected to have an accumulated funding deficiency within six plan years after the plan year beginning July 1, 2013. Even though the 1974 Plan is projected to have an accumulated funding deficiency within six plan years after the plan year beginning July 1, 2013, it is expected to have sufficient assets to pay benefits and expenditures during this time. In 2012, a funding improvement plan was sent to all participating companies for adoption. In 2013, an updated funding improvement plan was sent to all participating companies for adoption. The goals of the funding improvement plan are to improve the funded status and to avoid an accumulated funding deficiency for all plan years in the funding improvement period. The funding improvement plan provides increased contribution rates beginning in 2017 provided the funded status remains below the percentage noted above. The Plan’s funded status is reviewed annually by the certifying actuary. For the years ended December 31, 2014, 2013, and 2012, the Company incurred expenses related to the 1974 Plan of $19,204, $21,282, and $23,102. The contributions to the 1974 Plan made by two of the Company’s wholly-owned subsidiaries, Cumberland Coal Resources, LP and Emerald Coal Resources, LP, represent more than 5% of the total contributions to the 1974 Plan.
In connection with the Massey Acquisition and the Foundation Merger, the Company assumed obligations to the Coal Industry Retiree Health Benefit Act of 1992 (“Coal Act”), that provides for the funding of medical and death benefits for certain retired members of the UMWA through premiums to be paid by assigned operators (former employers). The Company treats its obligations under the Coal Act as participation in a multi-employer plan and recognizes the expense as premiums are paid. Expense relative to premiums paid for the years ended December 31, 2014, 2013, and 2012 was $802, $1,392 and $1,540, respectively. As required under the Coal Act, the Company’s obligation to pay retiree medical benefits to its UMWA retirees is secured by letters of credit in the amount of $8,249 as of December 31, 2014.
(d)    Workers’ Compensation and Pneumoconiosis (Black lung)
The Company is required by federal and state statutes to provide benefits to employees for awards related to workers’ compensation and black lung. In addition, as a result of the Massey Acquisition and the Foundation Merger, the Company assumed obligations related to providing workers’ compensation and black lung benefits to certain employees. The Company’s subsidiaries are insured for worker’s compensation and black lung obligations by a third-party insurance provider with the exception of certain subsidiaries where we are a qualified self-insurer for workers’ compensation and/or black lung related obligations, and with the exception of Wyoming where the Company participates in a compulsory state-run fund for workers’ compensation. Certain of the Company’s subsidiaries are self-insured for black lung benefits and may fund benefit payments through a Section 501(c)(21) tax-exempt trust fund.
The liability for self-insured workers’ compensation claims is an actuarially determined estimate of the undiscounted ultimate losses to be incurred on such claims based on the Company’s experience, and includes a provision for incurred but not reported losses. The liability for self-insured black lung benefits is estimated by an independent actuary by prorating the accrual of actuarially projected benefits over the employee's applicable term of service. Adjustments to the probable ultimate liability for workers’ compensation and black lung are made annually based on actuarial valuations.
For the Company’s subsidiaries that are fully insured for workers’ compensation and black lung claims, the insurance premium expense for the years ended December 31, 2014, 2013, and 2012 was $33,321, $29,068, and $42,566, respectively.
For the Company’s subsidiaries that are self-insured for workers’ compensation claims, the liability at December 31, 2014 and 2013 was $149,464 and $156,726, respectively, including a current portion of $11,640 and $14,189, respectively. Self-insured workers’ compensation expense for the years ended December 31, 2014, 2013, and 2012 was $12,186, $12,399, and $3,271, respectively. Certain of the Company’s subsidiaries’ self-insured workers’ compensation obligations are secured by letters of credit in the amount of $98,023 and surety bonds in the amount of $11,204. In addition, certain of the Company’s subsidiaries’ self-insured workers’ compensation obligations are secured by $7,388 of deposits.
The following tables set forth the accumulated black lung benefit obligations, fair value of plan assets and funded status for the years ended December 31, 2014 and 2013:
	December 31,
	2014				2013
Change in benefit obligation:
Accumulated benefit obligation at beginning of period	$	156,608			$	145,271
Service cost	2,199				2,708
Interest cost	7,125				6,577
Actuarial loss	7,417				11,294
Benefits paid	(9,010		)		(9,242		)
Plan amendments	6,336				—
Accumulated benefit obligation at end of period	$	170,675			$	156,608
Change in fair value of plan assets:
Fair value of plan assets at beginning of period	$	12,009			$	3,431
Actual return on plan assets	13				(19		)
Benefits paid	(9,010		)		(9,242		)
Employer contributions	9,053				17,839
Fair value of plan assets at end of period (1)	12,065				12,009
Funded status	(158,610		)		(144,599		)
Accrued benefit cost at end of year	$	(158,610	)		$	(144,599	)
Amounts recognized in the consolidated balance sheets:
Current liabilities	$	13,716			$	8,142
Long-term liabilities	144,894				136,457
	$	158,610			$	144,599
(1)	Assets of the plan are held in a Section 501(c)(21) tax-exempt trust fund and consist primarily of government debt securities. All assets are classified as Level 1 and valued based on quoted market prices.
Gross amounts related to the black lung obligations recognized in accumulated other comprehensive (income) loss consisted of the following as of December 31, 2014 and 2013:
	December 31,
	2014				2013
Prior service cost	$	6,336			$	—
Net actuarial loss	25,559				18,146
Accumulated Other Comprehensive Income	$	31,895			$	18,146
The following table details the components of the net periodic benefit cost for black lung obligations:
	Years Ended December 31,
	2014				2013			2012
Service cost	$	2,199			$	2,708		$	8,114
Interest cost	7,125				6,577			5,612
Expected return on plan assets	(257		)		(87		)	(52		)
Amortization of net actuarial loss	248				868			—
Net periodic expense	$	9,315			$	10,066		$	13,674
Other changes in the black lung plan assets and benefit obligations recognized in other comprehensive (income) loss are as follows:
	Years Ended December 31,
	2014				2013			2012
Current year actuarial loss (gain)	$	7,661			$	11,400		$	(19,154	)
Amortization of net actuarial loss	(248		)		(868		)	—
Current year prior service cost	6,336				—			—
Total recognized in other comprehensive (income) loss	$	13,749			$	10,532		$	(19,154	)
Total recognized in net periodic benefit cost and other comprehensive loss(income)	$	23,064			$	20,598		$	(5,480	)
The weighted-average assumptions related to black lung obligations used to determine the benefit obligation as of December 31, 2014 and 2013 were as follows:
	2014			2013
Discount rate	3.89	%		4.74%
Rate of increase in future compensation	3	%		3.00%
The weighted-average assumptions related to black lung obligations used to determine net periodic benefit cost were as follows:
	Years Ended December 31,
	2014		2013		2012
Discount rate	4.60%		4.14%		4.14%
Rate of increase in future compensation	3.00%		3.00%		3.00%
Expected long-term return on plan assets	3.00%		3.00%		3.00%
Estimated future cash payments related to black lung obligations for the next ten years ending after December 31, 2014 are as follows:
Year ending December 31:
2015	$	13,716
2016	8,697
2017	8,905
2018	9,013
2019	9,145
2019-2023	47,698
	$	97,174
(e)    Defined Contribution and Profit Sharing Plans
The Company sponsors multiple defined contribution and profit sharing plans to assist its eligible employees in providing for retirement. Generally, under the terms of these plans, employees make voluntary contributions through payroll deductions and the Company makes matching and/or discretionary contributions, as defined by each plan. The Company’s total contributions to these plans for the years ended December 31, 2014, 2013, and 2012 were $680, $48,327, and $79,257, respectively.
(f)    Self-Insured Medical Plan
Certain subsidiaries of the Company are principally self-insured for health insurance coverage provided for all of its active employees. Estimated liabilities for health and medical claims are recorded based on the Company’s historical experience and include a component for incurred but not reported claims. During the years ended December 31, 2014, 2013, and 2012, the Company incurred total claims expense of $176,204, $199,257, and $219,707, respectively, which represents claims processed and an estimate for claims incurred but not reported.

StockBased_Compensation_Awards

Stock-Based Compensation Awards	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation Awards	Stock-Based Compensation Awards
	On May 22, 2014, the Company's stockholders approved the Amended and Restated 2012 Long-Term Incentive Plan (the “2012 LTIP”). The principal purpose of the 2012 LTIP is to advance the interests of the Company and its stockholders by providing incentives to certain eligible persons who contribute significantly to the strategic and long-term performance objectives and growth of the Company. On May 22, 2014, the Company's stockholders approved an additional 3,100,000 shares of common stock for issuance under the 2012 LTIP Plan. The 2012 LTIP is currently authorized for the issuance of awards of up to 13,100,000 shares of common stock, and as of December 31, 2014, 4,188,180 shares of common stock were available for grant under the plan. The 2012 LTIP provides for a variety of awards, including options, stock appreciation rights, restricted stock, restricted share units (both time-based and performance-based), and any other type of award deemed by the Compensation Committee in its discretion to be consistent with the purpose of the 2012 LTIP. Prior to the approval of the 2012 LTIP, the Company issued awards under the 2010 Long Term Incentive Plan (the “2010 LTIP”) and the Alpha Appalachia 2006 Stock and Incentive Compensation Plan (the “2006 SICP”). Upon approval of the 2012 LTIP, no additional awards were issued or are able to be issued under the 2010 LTIP or the 2006 SICP. The 2012 LTIP, the 2010 LTIP and the 2006 SICP are collectively referred to as the “Stock Plans.” The Company also has stock-based awards outstanding under the Alpha Natural Resources, Inc. 2005 Long-Term Incentive Plan (the “2005 LTIP”) and the Foundation Amended and Restated 2004 Stock Incentive Plan (the “2004 SIP”).
	Upon vesting of restricted share units (both time-based and performance-based) or the exercise of options, shares are issued from the 2012 LTIP, the 2010 LTIP, the 2006 SICP, the 2005 LTIP, and the 2004 SIP, respective of which plan the awards were granted.
	The Company is authorized to repurchase common shares from employees (upon the election by the employee) to satisfy the employees’ minimum statutory tax withholdings upon the vesting of restricted stock and restricted share units (both time-based and performance-based). Shares that are repurchased to satisfy the employees’ minimum statutory tax withholdings are recorded in treasury stock at cost. During the years ended December 31, 2014, 2013, and 2012, the Company repurchased 311,437, 178,195, and 441,923, respectively, of common shares from employees at an average price paid per share of $4.69, $8.05, and $16.99, respectively.
	At December 31, 2014, the Company had three types of stock-based awards outstanding: restricted share units (both time-based and performance-based), restricted cash units (both time-based and performance-based), and stock options. Stock-based compensation expense totaled $27,371, $25,873, and $9,881, for the years ended December 31, 2014, 2013, and 2012, respectively. For the years ended December 31, 2014, 2013, and 2012, approximately 77%, 78%, and 51%, respectively, of stock-based compensation expense was reported as selling, general and administrative expenses and the remainder was recorded as cost of coal sales. The total excess tax benefit recognized for stock-based compensation was $0 for the years ending December 31, 2014, 2013, and 2012.
	Restricted Stock Awards
	No awards were granted during the years ended December 31, 2014, 2013 and 2012 and no awards were outstanding as of December 31, 2014. The fair value of restricted stock awards that vested for the years ended December 31, 2014, 2013, and 2012 was $0, $0, and $11,142, respectively. As of December 31, 2014, there was no unrecognized compensation cost related to non-vested restricted stock awards.
	Restricted Share Units
	Time-Based Share Units
	Time-based share units awarded to executive officers and key employees generally vest, subject to continued employment, ratably over three-year periods or cliff vest after three years from grant (with accelerated vesting in certain instances, including in the event of a qualifying employment termination in connection with a change of control). Time-based share units currently granted to the Company’s non-employee directors generally vest on the one-year anniversary of grant (with accelerated vesting in certain circumstances, including in connection with a change of control). Upon vesting of time-based share units, the Company issues authorized and unissued shares of the Company’s common stock to the recipient.
	During the years ended December 31, 2014, 2013, and 2012, the Company granted time-based share units under the 2012 LTIP to certain executive officers, directors and key employees in the amount of 1,632,824, 1,752,075, and 1,016,733, respectively, of which 3,413,160 remained outstanding as of December 31, 2014. Additionally, during the year ended December 31, 2014, the Company also awarded certain of its executives and key employees 2,077,491 time-based cash units which are accounted for as liability awards and subject to variable accounting of which 1,919,680 remained outstanding as of December 31, 2014. The liability for these awards totaled $1,305 as of December 31, 2014.
	During the year ended December 31, 2012, the Company granted time-based share units under the 2006 SICP to certain executive officers, directors and key employees in the amount of 146,044, of which 62,161 remained outstanding at December 31, 2014.
	During the year ended December 31, 2012, the Company granted time-based share units under the 2010 LTIP to certain executive officers, directors and key employees in the amount of 706,564 of which 199,733 remained outstanding at December 31, 2014.
	Time-based share unit activity for the year ended December 31, 2014 is summarized in the following table:
		Number of		Weighted-
		Shares		Average
				Grant Date
				Fair Value
	Non-vested shares outstanding at December 31, 2013	3,099,289		$	11.66
	Granted	1,632,824		$	4.25
	Vested	(906,424	)	$	16.26
	Forfeited or Expired	(57,256	)	$	10.34
	Non-vested shares outstanding at December 31, 2014	3,768,433		$	7.32
	Time-based cash unit activity for the year ended December 31, 2014 is summarized in the following table:
		Number of		Weighted-
		Shares		Average
				Fair Value (1)
	Non-vested shares outstanding at December 31, 2013	—		—
	Granted	2,077,491		4.38
	Vested	(98,335	)	2.46
	Forfeited/Expired	(59,476	)	2.28
	Non-vested shares outstanding at December 31, 2014	1,919,680		1.67
	(1) The time-based cash units are accounted for as liability awards and subject to variable accounting. Therefore, the weighted-average fair value is calculated using the Company's stock price at the respective granted date, vested date and forfeited/expired date.
	The fair value of time-based share unit awards that vested in the years ended December 31, 2014, 2013, and 2012 was $4,470, $4,536, and $13,775, respectively. As of December 31, 2014, there was $6,833 of unrecognized compensation cost related to non-vested time-based share units which is expected to be recognized as expense over a weighted-average period of 1.45 years. Additionally, as of December 31, 2014, there was $1,906 of unrecognized compensation cost related to non-vested time-based cash units which is expected to be recognized as expense over a weighted-average period of 2.15 years. The unrecognized compensation cost, related to non-vested time-based cash units which are accounted for as liability awards and subject to variable accounting, was calculated using the Company's December 31, 2014 stock price and will fluctuate with future changes in the Company's stock price.
	Performance-Based Share Units
	Performance-based share units awarded to executive officers and key employees generally cliff vest after three years, subject to continued employment (with accelerated vesting upon a change of control). Performance-based share units granted represent the number of shares of common stock to be awarded based on the achievement of targeted performance levels related to pre-established operating income goals, strategic goals, total shareholder return goals, and cash flow from operations goals over a three year period and may range from 0 percent to 200 percent of the targeted amount. The grant date fair value of the awards with performance conditions is based on the closing price of the Company’s common stock on the established grant date and is amortized over the performance period. The grant date fair value of the awards with market conditions is based upon a Monte Carlo simulation and is amortized over the performance period. For awards with performance conditions, the Company reassesses at each reporting date whether achievement of each of the performance conditions is probable, as well as estimated forfeitures, and adjusts the accruals of compensation expense as appropriate. For awards with market conditions, the Company recognizes expense over the applicable service periods and does not adjust expense based on the actual achievement or nonachievement of the market condition because the probability of achievement is considered in the grant date fair value of the award. Upon vesting of performance-based share units, the Company issues authorized and unissued shares of the Company’s common stock to the recipient.
	During 2014, the Company awarded 1,378,486 performance-based share units, of which 1,372,140 remain outstanding as of December 31, 2014. As of December 31, 2014, there was $4,194 of unrecognized compensation cost related to the 2014 performance-based share units which is expected to be recognized as expense over a weighted-average period of 2 years. Additionally, during the year ended December 31, 2014, the Company also awarded certain of its executives and key employees 1,378,486 performance-based cash units which are accounted for as liability awards and subject to variable accounting, of which 1,372,140 remain outstanding as of December 31, 2014. At December 31, 2014, the Company had assessed the cash flow performance target as not probable of achievement. Therefore, the liability for these awards totaled $0 with no unrecognized compensation cost as of December 31, 2014.
	During 2013, the Company awarded 1,531,787 performance-based share units, of which 1,497,482 remain outstanding as of December 31, 2014. At December 31, 2014, the cash flow performance target was achieved. As of December 31, 2014, there was $6,475 of unrecognized compensation cost related to the 2013 performance-based share units which is expected to be recognized as expense over a weighted-average period of 1.00 years.
	During 2012, the Company awarded 1,149,392 performance-based share units, of which 1,044,659 remain outstanding as of December 31, 2014. At December 31, 2014, there was no unrecognized compensation cost related to the 2012 performance-based share units expected to be recognized as expense due to the Company’s assessment of probability of achievement of performance targets.
	Performance-based share unit activity for the year ended December 31, 2014 is summarized in the following table:
		Number of		Weighted-
		Shares (1)		Average
				Grant Date
				Fair Value
	Non-vested shares outstanding at December 31, 2013	5,566,158		$	15.25
	Granted	2,756,972		$	4.33
	Earned	(11,027	)	$	2.6
	Forfeited or expired	(493,472	)	$	58.6
	Non-vested shares outstanding at December 31, 2014	7,818,631		$	8.78
	(1)  Shares in the table above are based on the maximum shares that can be awarded based on the achievement of the performance criteria. The fair value of performance-based share unit awards granted in 2009 and vested on February 22, 2012 was $4,937.
	Performance-based cash unit activity for the year ended December 31, 2014 is summarized in the following table:
		Number of		Weighted-
		Shares (1)		Average
				Fair Value (2)
	Non-vested shares outstanding at December 31, 2013	—		—
	Granted	2,756,972		4.33
	Earned	—		—
	Forfeited or expired	(12,692	)	3.37
	Non-vested shares outstanding at December 31, 2014	2,744,280		1.67
	(1)  Shares in the table above are based on the maximum shares that can be awarded based on the achievement of the performance criteria.
	(2) The performance-based cash units are accounted for as liability awards and subject to variable accounting. Therefore, the weighted-average fair value is calculated using the Company's stock price at the respective granted date, vested date, forfeited/expired date, and outstanding dates.
	Non-Qualified Stock Options
	Stock option activity for the year ended December 31, 2014 is summarized in the following table:
		Number of		Weighted-			Weighted-
Shares		Average		Average
		Exercise		Remaining
		Price		Contractual
				Term (Years)
Outstanding at December 31, 2013	937,977		$	21.77
Exercised	—		$	—
Forfeited or Expired	(351,255	)	$	15.58
Outstanding at December 31, 2014	586,722		$	25.48		3.41
Exercisable at December 31, 2014	586,722		$	25.48		3.41
As of December 31, 2014, the options outstanding and exercisable had an aggregate intrinsic value of $0. Cash received from the exercise of stock options during the years ended December 31, 2014, 2013, and 2012 was $0, $0, and $176, respectively. As of December 31, 2014, there was no unrecognized compensation cost related to stock options.
The total intrinsic value of options exercised during the years ended December 31, 2014, 2013, and 2012 was $0, $0, and $253, respectively. The Company currently uses authorized and unissued shares to satisfy share award exercises.
A summary of the Company’s options outstanding and exercisable at December 31, 2014 follows:
		Options Outstanding and Exercisable
Exercise		Shares		Weighted-	Weighted-
Price				Average	Average
				Remaining	Exercise
				Life (yrs)	Price
$ 11.15-$20.44		278,429		2.39	$	17.42
$ 23.93-$32.91		199,518		3.52	$	28.29
$ 40.98-$48.26		108,775		5.88	$	41.04
		586,722		3.41	$	25.48

Related_Party_Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions
	For the years ended December 31, 2014, 2013, and 2012, there were no material related party transactions.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies
	(a) General
	Estimated losses from loss contingencies are accrued by a charge to income when information available indicates that it is probable that an asset has been impaired or a liability has been incurred and the amount of the loss can be reasonably estimated. If a loss contingency is not probable or reasonably estimable, disclosure of the loss contingency is made in the consolidated financial statements when it is at least reasonably possible that a loss may be incurred and that the loss could be material.
	(b) Commitments and Contingencies
	Commitments
	The Company leases coal mining and other equipment under long-term capital and operating leases with varying terms. In addition, the Company leases mineral interests and surface rights from land owners under various terms and royalty rates.
	As of December 31, 2014, aggregate future minimum non-cancelable lease payments under operating leases and minimum royalties under coal leases were as follows:
		Operating			Coal
		Leases			Royalties
	Year Ending December 31:
	2015	$	5,282		$	38,494
	2016	793			35,192
	2017	150			33,669
	2018	—			25,546
	2019	—			13,450
	Thereafter	—			65,215
	Total	$	6,225		$	211,566
	For the years ended December 31, 2014, 2013, and 2012, net rent expense under operating leases was $25,895, $44,087, and $81,021 respectively, and coal royalty expense was $214,599, $222,875, and $336,068 respectively.
	The following is a schedule by years of future minimum lease payments under capital leases together with the present value of the net minimum lease payments as of December 31, 2014:
		Capital Leases
	Year Ending December 31:
	2015	$	19,311
	2016	12,067
	2017	9,966
	2018	3,057
	2019	2,962
	Thereafter	48,479
	Total minimum lease payments	$	95,842
	Less: Amount representing interest (rates range from 0.15% to 13.86%)	(44,480		)
	Present value of net minimum lease payments	$	51,362
	Other Commitments
	In September 2011, the Company entered into a federal coal lease, which contained an estimated 130.2 million tons of proven and probable coal reserves in the Powder River Basin. The lease bid was $143,415, payable in five equal annual installments of $28,683. The first installment was paid in September 2011. In August 2012, the Company entered into an agreement with a third party to exchange this federal coal lease for a federal coal lease from a third party, which contains an estimated 222 million tons of proven and probable coal reserves in the Powder River Basin adjacent to the Company’s existing mining operations. As a result of the exchange the Company paid $17,392 at closing and has four annual remaining lease bid installments of $42,130 due each November until the obligation is satisfied in 2015. Three of these installments were paid in November 2012, 2013, and 2014. Also as a result of the exchange, the Company recorded a note payable, which had a present value of $3,469 as of December 31, 2014, all of which is recorded as current portion of long-term debt in the Company’s Consolidated Balance Sheet as of December 31, 2014. The note is payable in four annual installments of $3,946 due each November through 2015. The Company paid the first three installments in November 2012, 2013, and 2014.
	The Company also has obligations under certain coal transportation agreements that contain minimum quantities to be shipped each year. Minimum amounts due under these contracts for the next five years and beyond are $16,478, $64,961, $17,540, $12,930, $66,120 and $213,056 respectively.
	Contingencies
	Extensive regulation of the impacts of mining on the environment and of maintaining workplace safety, and related litigation, has had or may have a significant effect on the Company’s costs of production and results of operations. Further regulations, legislation or litigation in these areas may also cause the Company’s sales or profitability to decline by increasing costs or by hindering the Company’s ability to continue mining at existing operations or to permit new operations.
	During the normal course of business, contract-related matters arise between the Company and its customers. When a loss related to such matters is considered probable and can reasonably be estimated, the Company records a liability. During the year ended December 31, 2013, the Company recorded a gain of ($55,454) in other expenses in the Consolidated Statement of Operations related to the resolution of a contract-related matter.
	(c) Guarantees and Financial Instruments with Off-Balance Sheet Risk
	In the normal course of business, the Company is a party to certain guarantees and financial instruments with off-balance sheet risk, such as bank letters of credit, performance or surety bonds, and other guarantees and indemnities related to the obligations of affiliated entities which are not reflected in the Company’s Condensed Consolidated Balance Sheets. The Company is self bonded with respect to certain performance obligations, including reclamation, for $676,149. Management does not expect any material losses to result from these guarantees or other off-balance sheet financial instruments.
	Letters of Credit
	As of December 31, 2014, the Company had $177,249 of letters of credit outstanding under its revolving credit facility, and $34,969 of letters of credit outstanding under its account receivable securitization facility.
	(d) Legal Proceedings
	The Company’s legal proceedings range from cases brought by a single plaintiff to purported class actions. These legal proceedings, as well as governmental examinations, involve various business units and a variety of claims including, but not limited to, contract disputes, personal injury claims, property damage claims (including those resulting from blasting, trucking and flooding), environmental and safety issues, and employment matters. While some matters pending against the Company or its subsidiaries specify the damages claimed by the plaintiffs, many seek an unquantified amount of damages or are at very early stages of the legal process. Even when the amount of damages claimed against the Company or its subsidiaries is stated, (i) the claimed amount may be exaggerated or unsupported; (ii) the claim may be based on a novel legal theory or involve a large number of parties; (iii) there may be uncertainty as to the likelihood of a class being certified or the ultimate size of the class; (iv) there may be uncertainty as to the outcome of pending appeals or motions; and/or (v) there may be significant factual issues to be resolved. As a result, the Company may be unable to estimate a range of possible loss for matters that have not yet progressed sufficiently through discovery and development of important factual information and legal issues. Other matters have progressed sufficiently that the Company is able to estimate a range of possible loss. Accordingly, for those legal proceedings and governmental examinations disclosed below as to which a loss is reasonably possible in future periods and for which the Company is able to estimate a range of possible loss, the current estimated range is up to $100,000 in excess of the accrued liability (if any) related to those matters. This aggregate range represents the Company’s estimate of additional possible loss in excess of the accrued liability (if any) with respect to these matters and net of third party indemnification arrangements (if any, other than insurance) as described below related to those matters, based on currently available information, including any damages claimed by the plaintiffs, and is subject to significant judgment and a variety of assumptions and inherent uncertainties. For example, at the time of making an estimate, the Company may have only preliminary, incomplete, or inaccurate information about the facts underlying a claim; its assumptions about the future rulings of the court or other tribunal on significant issues, or the behavior and incentives of adverse parties, regulators, indemnitors or co-defendants, may prove to be wrong; and the outcomes it is attempting to predict are often not amenable to the use of statistical or other quantitative analytical tools. In addition, from time to time an outcome may occur that the Company had not accounted for in its estimate because it had considered that outcome to be remote. Furthermore, as noted above, the aggregate range does not include any matters for which the Company is not able to estimate a range of possible loss. Accordingly, the estimated aggregate range of possible loss does not represent the Company’s maximum loss exposure. The legal proceedings and governmental examinations underlying the estimated range will change from time to time, and actual results may vary significantly from the current estimate. The Company intends to defend these legal proceedings vigorously, litigating or settling cases where in the Company’s judgment it would be in the best interest of shareholders to do so.
	For purposes of FASB ASC Topic 450 (“ASC 450”), an event is “reasonably possible” if “the chance of the future event or events occurring is more than remote but less than likely” and an event is “remote” if “the chance of the future event or events occurring is slight.” ASC 450 requires accrual for a liability when it is (a) “probable that one or more future events will occur confirming the fact of loss” and (b) “the amount of loss can be reasonably estimated.” If a range of loss is estimated, the best estimate within the range is required to be accrued. If no amount within the range is a better estimate, the minimum amount of the range is required to be accrued.
	The Company evaluates, on a quarterly basis, developments in legal proceedings and governmental examinations that could cause an increase or decrease in the amount of the reserves previously recorded. Excluding fees paid to external legal counsel, the Company recognized (income) expense, net of expected insurance recoveries, associated with litigation-related reserves of ($11,604), $212,233 and $15,406 during the years ended December 31, 2014, 2013 and 2012, respectively.
	UBB Explosion and Related Investigations and Litigation
	On April 5, 2010, before the Massey Acquisition by the Company, an explosion occurred at the Upper Big Branch (“UBB”) mine, resulting in the deaths of twenty-nine miners. The Federal Mine Safety and Health Administration (“MSHA”), the Office of Miner’s Health, Safety, and Training of the State of West Virginia (“State”), and the Governor’s Independent Investigation Panel (“GIIP”) initiated investigations into the cause of the UBB explosion and related issues. Additionally, the United States Attorney for the Southern District of West Virginia (the “Office”) commenced a grand jury investigation. The GIIP published its final report on May 19, 2011; MSHA released its final report on December 6, 2011; and the State released its final report on February 23, 2012. The Company cannot predict whether or not any individual will become subject to possible criminal and civil penalties or enforcement actions as a result of these investigations.
	The UBB mine was idled in order to accommodate these investigations. On April 20, 2012, the Company was authorized by regulatory authorities to close the UBB mine permanently, and on June 19, 2012, the sealing of the mine was completed.
	Non-Prosecution Agreement
	On December 6, 2011, the Company, the Office and the United States Department of Justice entered into a Non-Prosecution Agreement (the “Agreement”) resolving the criminal investigation against Massey and its affiliates relating to the UBB explosion and other health and safety related issues at Massey, and the Company also reached a comprehensive settlement with MSHA resolving outstanding civil citations, violations, and orders related to MSHA’s investigation arising from the UBB explosion and other non-UBB related matters involving legacy Massey entities prior to the Massey Acquisition. The Agreement did not resolve individual responsibilities related to the UBB explosion.
	Under the terms of the Agreement and MSHA settlement, the Company agreed to pay outstanding MSHA fines, and agreed to invest in additional measures designed to improve miner health and safety, provide restitution to the families of the fallen miners and two individuals injured in the UBB explosion, and create a charitable organization to research mine safety. The Company further agreed to cooperate fully with all governmental agencies in all continuing investigations and prosecutions against any individuals that arise out of the UBB explosion and related conduct described in the Agreement until such investigations and prosecutions are concluded.
	On February 10, 2014, the Company announced that it had fully complied with the terms of the Agreement and that the Office and the United States Department of Justice had closed the Agreement.
	Purported Securities Class Action Suits
	In 2010, two purported class actions that were subsequently consolidated into one case were brought against, among others, Massey, now the Company’s subsidiary Alpha Appalachia Holdings, Inc. (“Alpha Appalachia”), in the United States District Court for the Southern District of West Virginia (the “Court”) in connection with alleged violations of the federal securities laws. The lead plaintiffs alleged that (i) Massey and certain former Massey directors and officers violated Section 10(b) of the Securities and Exchange Act of 1934, as amended, (the “Exchange Act”), and Rule 10b-5 thereunder and that (ii) Massey’s former officers violated Section 20(a) of the Exchange Act by virtue of their control over persons alleged to have committed violations of Section 10(b) of the Exchange Act.
	In 2014, the parties reached agreement on definitive settlement terms, subject to court approval. In February 2014, the Court entered an order preliminarily approving the settlement, following which the Company made an initial payment of $30,000 into an escrow account. In June 2014, the Company deposited the remaining $235,000 of the settlement amount into the escrow account. On June 4, 2014, the Court entered an order approving the settlement and dismissed the class action with prejudice. The Company received approximately $70,000 of insurance proceeds in connection with the settlement.
	Wrongful Death and Personal Injury Suits
	Subsequently, twenty of the twenty-nine families of the deceased miners filed wrongful death suits against Massey and certain of its subsidiaries in West Virginia, in Boone County Circuit Court and Wyoming County Circuit Court. In addition, two seriously injured employees filed personal injury claims against Massey and certain of its subsidiaries in Boone County Circuit Court seeking damages for physical injuries and/or alleged psychiatric injuries, and thirty-nine employees filed lawsuits against Massey and certain of its subsidiaries in Boone County Circuit Court and Wyoming County Circuit Court alleging emotional distress or personal injuries due to their proximity to the explosion.
	Through mediation ordered by the Boone County Circuit Court, the Company reached agreements to settle with all twenty-nine families of the deceased miners, the two employees who were seriously injured and thirty-nine employees who filed lawsuits for emotional distress or personal injuries. The settlements reached with the families of the deceased miners were approved by the court, and the other settlements did not require court approval.
	On April 5, 2012, the family of one of the deceased miners filed a class action suit in Boone County Circuit Court, purportedly on behalf of the families that settled their claims prior to the mediation, alleging fraudulent inducement into a contract, naming as defendants Massey, the Company and certain of its subsidiaries, the Company’s CEO and the Company’s Board of Directors.
	On June 17, 2013 and August 29, 2013, two complaints were filed in Boone County Circuit Court alleging personal injury claims relating to the UBB explosion. In July 2014, the Circuit Court granted the Company's motion to dismiss in one of the two cases. The second motion was denied in October 2014.
	On July 17, 2013, the administrators for the estates of three miners who died in the UBB explosion filed an action against Alpha and Alpha Appalachia in the United States District Court for the Southern District of West Virginia claiming they are entitled “criminal restitution” under the Agreement, which defendants moved to dismiss. In October 2013, the court granted defendants’ motion to dismiss the complaint with prejudice. The plaintiffs appealed this dismissal order. In September 2014, the Court of Appeals determined that the plaintiffs had failed to establish that the District Court had jurisdiction over the case. Accordingly, the Court of Appeals vacated the District Court’s dismissal of the case and remanded the case with instructions to dismiss the case without prejudice for lack of jurisdiction. On October 22, 2014, the District Court entered an order dismissing the plaintiffs’ complaint without prejudice and terminating all pending motions as moot.
	Plaintiffs filed a new complaint on November 7, 2014. Defendants subsequently filed a motion to dismiss and plaintiffs filed a motion for leave to file a surreply memorandum. These motions remain pending before the District Court.
	Delaware Chancery Court Derivative Suit
	In a case filed on April 23, 2010 in Delaware Chancery Court, In re Massey Energy Company Derivative and Class Action Litigation (“In re Massey”), a number of purported former Massey stockholders (the “Delaware Plaintiffs”) allege, purportedly on behalf of Massey, that certain former Massey directors and officers breached their fiduciary duties by failing to monitor and oversee Massey’s employees, allegedly resulting in fines against Massey and the explosion at UBB, and by wasting corporate assets by paying allegedly excessive and inflated amounts to former Massey Chairman and Chief Executive Officer Don L. Blankenship as part of his retirement package. The Delaware Plaintiffs also allege, on behalf of a purported class of former Massey stockholders, that certain former Massey directors breached their fiduciary duties by agreeing to the Massey Acquisition. The Delaware Plaintiffs allege that defendants breached their fiduciary duties by failing to secure the best price possible, by failing to secure any downside protection for the acquisition consideration, and by purportedly eliminating the possibility of a superior proposal by agreeing to a “no shop” provision and a termination fee. In addition, the Delaware Plaintiffs allege that defendants agreed to the Massey Acquisition to eliminate the liability that defendants faced on the Delaware Plaintiffs’ derivative claims. Finally, the Delaware Plaintiffs allege that defendants failed to fully disclose all material information necessary for Massey stockholders to cast an informed vote on the Massey Acquisition.
	The Delaware Plaintiffs also name the Company and Mountain Merger Sub, Inc. (“Merger Sub”), the Company’s wholly-owned subsidiary created for purposes of effecting the Massey Acquisition, which, at the effective time of the Massey Acquisition, was merged with and into Massey, as defendants. The Delaware Plaintiffs allege that the Company and Merger Sub aided and abetted the former Massey directors’ alleged breaches of fiduciary duty and agreed to orchestrate the Massey Acquisition for the purpose of eliminating the former Massey directors’ potential liability on the derivative claims. Two additional putative class actions were brought against Massey, certain former Massey directors and officers, the Company and Merger Sub in the Delaware Court of Chancery following the announcement of the Massey Acquisition, which were consolidated for all purposes with In re Massey in February 2011.
The Delaware Plaintiffs seek an award against each defendant for restitution and/or compensatory damages, plus pre-judgment interest; an order establishing a litigation trust to preserve the derivative claims asserted in the complaint; and an award of costs, disbursements and reasonable allowances for fees incurred in this action. The Delaware Plaintiffs also sought to enjoin consummation of the Massey Acquisition. The court denied their motion for a preliminary injunction in May 2011.
In June 2011, Massey moved to dismiss the Delaware Plaintiffs’ derivative claims on the ground that the Delaware Plaintiffs, as former Massey stockholders, lacked the legal right to pursue those claims, and the Company and Alpha Appalachia Merger Sub moved to dismiss the purported class action claim against them for failure to state a claim upon which relief may be granted. In June 2011, certain former Massey director and officer defendants moved to dismiss the derivative claims and filed answers to the remaining direct claims.
In September 2011, the parties submitted a Stipulation Staying Proceedings, which stayed the matter until March 2012, without prejudice to the parties’ right to seek an extension or a termination of the stay by application to the court. The court approved the stipulation and entered the stay that same day. The court extended the stay several times and the most recent stay expired on October 31, 2014.
On October 17, 2014, the Delaware Plaintiffs filed an amended complaint which maintains claims against Massey and certain former Massey directors and officers but no longer asserts claims against the Company or Mountain Merger Sub, Inc. Defendants moved to dismiss on December 5, 2014, and the motion remains pending.
West Virginia State Court Derivative Suit
In a case filed on April 15, 2010 in West Virginia state court, three purported former Massey stockholders (the “West Virginia Plaintiffs”) allege, purportedly on behalf of Massey, that certain former Massey directors and officers breached their fiduciary duties by failing to monitor and oversee Massey’s employees, allegedly resulting in fines against Massey and the explosion at UBB. The West Virginia Plaintiffs seek an award against each defendant and in favor of Massey for the amount of damages sustained by Massey as a result of defendants’ alleged breaches of fiduciary duty and an award to the West Virginia Plaintiffs of the costs and disbursements of the action, including reasonable attorneys’ fees, accountants’ and experts’ fees, costs, and expenses.
In May 2011, the West Virginia Plaintiffs moved for leave to amend their complaint to add Alpha and Merger Sub as additional defendants and to add claims allegedly arising out of the then-proposed Massey Acquisition. In their proposed amended complaint, the West Virginia Plaintiffs allege that certain former Massey directors breached their fiduciary duties by failing to obtain the highest price reasonably available for Massey and by failing to disclose material information to Massey’s then-stockholders in connection with the stockholder vote on the Massey Acquisition. The West Virginia Plaintiffs also allege that Massey, Merger Sub and the Company aided and abetted the former Massey directors’ breaches of fiduciary duty. The West Virginia Plaintiffs further allege that certain former Massey directors wasted corporate assets by failing to maintain sufficient internal controls over Massey’s safety and environmental reporting; failing to properly consider the interests of Massey and its stockholders, including the value of the derivative claims asserted by the West Virginia Plaintiffs in the Massey Acquisition; failing to conduct proper supervision; paying undeserved incentive compensation to certain Massey executive directors, particularly former Massey Chairman and CEO Don L. Blankenship during Massey’s alleged years of noncompliance with safety regulations and more recently as part of Blankenship’s retirement package; incurring millions of dollars in fines due to safety and environmental violations; and incurring potentially hundreds of millions of dollars of legal liability and/or legal costs to defend defendants’ allegedly unlawful actions. Finally, the West Virginia Plaintiffs’ proposed amended complaint alleges that certain former Massey directors were unjustly enriched by their compensation as directors.
In June 2011, the defendants moved to dismiss the West Virginia Plaintiffs’ original complaint, or, alternatively, to stay the case in favor of In re Massey, described above. Defendants also filed an opposition to the West Virginia Plaintiffs’ motion to amend. In November 2013, the court denied the West Virginia Plaintiffs’ motion to amend and granted defendants’ motion to dismiss. The West Virginia Plaintiffs appealed the denial of motion to amend and dismissal to the Supreme Court of Appeals of West Virginia, which remanded the action to the Circuit Court. On November 20, 2014, the Circuit Court entered an order dismissing the suit with prejudice as to the individual defendants and nominal defendant Massey Energy Company (n/k/a Alpha Appalachia Holdings, Inc.). On December 22, 2014, plaintiffs appealed the order to the West Virginia Supreme Court of Appeals.
Advancement Action
On February 5, 2015, Donald Blankenship, former Massey Chief Executive Officer and Chairman of the Board of Directors, filed an action in Delaware Chancery Court against Alpha and its affiliate Alpha Appalachia Holdings, Inc. to contest the decision to terminate further advancement of legal fees for Mr. Blankenship in connection with his pending criminal trial in the Southern District of West Virginia. The action is a summary proceeding and a hearing has been scheduled for the week of April 5, 2015.
Mine Water Discharge Suits
Conductivity Suit
On March 20, 2012, three environmental groups filed a citizen’s suit against two of the Company’s subsidiaries, Alex Energy, Inc. (“Alex Energy”) and Elk Run Coal Company, Inc., in federal court in the Southern District of West Virginia. The suit alleged violations of the terms of the subsidiaries’ water discharge permits concerning conductivity levels, although the subject permits do not contain numerical limits on conductivity. The plaintiffs sought a civil penalty as well as injunctive relief. On June 4, 2014, the Court entered partial summary judgment against the subsidiaries.
On December 15, 2014, the parties reached agreement on definitive settlement terms, subject to court approval. The court approved the settlement on February 2, 2015. The settlement terms do not include a civil penalty and provide for a compliance deadline of August 1, 2019.
Selenium Suits
On May 9, 2012, three environmental groups filed a citizen’s suit in federal court in the Southern District of West Virginia against two of the Company’s subsidiaries alleging violations of the terms of the subsidiaries’ water discharge permits. The plaintiffs seek a civil penalty as well as injunctive relief. In 2014, the Court entered partial summary judgment against one of the subsidiaries.
On July 16, 2012, three environmental groups filed a citizen’s suit in federal court in the Southern District of West Virginia against seven of the Company’s subsidiaries alleging violations of the terms of the subsidiaries’ water discharge permits. On April 10, 2013, the Company’s subsidiary Bandmill Coal Co. (“Bandmill”) was served with a complaint from the Sierra Club and others, alleging discharges of selenium from the site of Bandmill’s former Tower Mountain surface mine into waters of the United States without a proper permit. These suits were consolidated in May 2013. The plaintiffs seek a civil penalty as well as injunctive relief. In 2014, the Court entered partial summary judgment against one of the subsidiaries.
On July 23, 2013, Alex Energy was served with a complaint alleging that discharges from the PGM No. 1 surface mine into Hardway Branch of Twentymile Creek violated state water quality standards for selenium. In July 2014, the Court entered partial summary judgment against Alex Energy.
On December 19, 2014, the Company announced the settlement of these three suits. As part of the settlement, the Company-affiliated mining operations will pay a civil penalty of $350 and have agreed to compliance dates that are largely consistent with existing permits or permit renewal proposals for these mining operations. The court approved the settlement on February 2, 2015.
On May 15, 2012, the West Virginia Department of Environmental Protection filed a civil enforcement action against the Company’s subsidiary Riverside Energy Company, LLC, in McDowell County Circuit Court in West Virginia seeking civil penalties and injunctive relief based on alleged discharge of selenium in excess of permitted levels. This case was mooted by the Company’s entry into the Consent Decree discussed below.
Other Matters
On December 31, 2012 and January 2, 2013, two separate environmental groups filed citizen’s suits in federal court in the Western District of Pennsylvania against Emerald Coal Resources, L.P., and other of the Company’s subsidiaries, alleging violations of the terms of the subsidiaries’ water discharge permits. The first of these cases has since been voluntarily dismissed by the plaintiffs. The plaintiffs in the remaining case seek a civil penalty as well as injunctive relief. This case is likely to be mooted by the Consent Decree, which is discussed below.
On March 27, 2013, Alex Energy was served with a complaint from the Sierra Club, and others, alleging improper discharges by Alex Energy into Spruce Run and Road Fork of Robinson Creek in Nicholas County, West Virginia. Alex Energy has appropriate permits for discharges into those tributaries, and the discharges discussed in the plaintiffs’ complaint are undertaken by Alex Energy in compliance with its permits.
On July 29, 2013, the Company’s subsidiary, Pigeon Creek Processing Co. (“Pigeon Creek”), was notified by environmental groups that they intend to sue Pigeon Creek for discharging selenium from the Stonega impoundment area without the proper authorization in the NPDES permit. To date, no suit has been filed in this matter.
On May 21, 2014, the Company’s subsidiary, Dickenson-Russell Coal Company (“DRCC”), was notified by environmental groups that they intend to sue DRCC for alleged discharges from the Moss #3 Preparation Plant in connection with wasteload allocations for total dissolved solids (TDS). To date, no suit has been filed.
Consent Decree
On March 5, 2014, Alpha entered into a consent decree (the “Consent Decree”) with the EPA, the U.S. Department of Justice and three states regarding claims under the Clean Water Act. The Consent Decree resolves a complaint by the EPA and state agencies in Kentucky, Pennsylvania and West Virginia alleging that the Alpha’s mining affiliates in those states and in Tennessee and Virginia exceeded certain water discharge permit limits during the period 2006 to 2013. As part of the Consent Decree, Alpha agreed to implement an integrated environmental management system and an expanded auditing/reporting protocol, install selenium and osmotic pressure treatment facilities at specific locations, and certain other measures. The Consent Decree also stipulates that Alpha will pay $27,500 in civil penalties, to be divided among the federal government and state agencies. On November 26, 2014, the Consent Decree was approved by the Court and Alpha subsequently paid the civil penalties.
Nicewonder Litigation
Affiliated Construction Trades Foundation Litigation
In December 2004, prior to the Company’s acquisition of Nicewonder in October 2005, the Affiliated Construction Trades Foundation (“ACTF”), a division of the West Virginia State Building and Construction Trades Council, brought an action against the West Virginia Department of Transportation, Division of Highways (“WVDOH”) and Nicewonder Contracting, Inc. (“NCI”), which became the Company’s wholly-owned indirect subsidiary as a result of the Nicewonder acquisition, in the Circuit Court of Kanawha County, West Virginia, which was removed to the United States District Court for the Southern District of West Virginia (the “ACTF Litigation”). The plaintiff sought a declaration that the contract between NCI and the State of West Virginia related to NCI’s road construction project for the Red Jacket section of the King Coal Highway (the “Red Jacket Contract”) was illegal as a violation of applicable West Virginia and federal competitive bidding and prevailing wage laws.
On September 30, 2009, the District Court issued an order that dismissed for lack of standing all of ACTF’s claims under federal law and remanded the remaining state claims to the Circuit Court of Kanawha County, West Virginia for resolution. On May 7, 2010, the Circuit Court of Kanawha County entered summary judgment in favor of NCI. On June 22, 2011, the West Virginia Supreme Court of Appeals reversed the Circuit Court order granting summary judgment in favor of NCI, and remanded the case back to the Circuit Court for further proceedings. Following remand, ACTF filed a motion for summary judgment, which the Circuit Court denied on November 9, 2011. ACTF challenged the order denying its summary judgment motion to the West Virginia Supreme Court of Appeals.
On June 21, 2012, the West Virginia Supreme Court of Appeals issued an opinion finding that ACTF had standing to pursue its claims and remanded the case back to the Circuit Court of Kanawha County, West Virginia for further proceedings.
A settlement between NCI and ACTF was agreed upon in early January 2013, prior to the January 14, 2013 trial date, and the Circuit Court subsequently dismissed the case as to NCI, with prejudice. The Company did not incur any out-of-pocket expenditures in connection with that settlement.
A bench trial proceeded among the remaining parties to the ACTF Litigation and, on February 26, 2013, the Circuit Court of Kanawha County entered an order that ruled against WVDOH in finding that the Red Jacket Contract, as well as the awarding and implementation of that contract, were in violation of West Virginia law because the Red Jacket Contract did not contain a provision whereby WVDOH required payment by NCI of statutory prevailing wages to employees; and WVDOH did not conduct a public bidding process before awarding the Red Jacket Contract to NCI. The time to appeal the order has passed without an appeal having been filed, and the order has become final.
NCI Employee Litigation
On February 7, 2013, the Company received notice of a putative class action lawsuit against NCI filed in the Circuit Court of Mingo County, West Virginia by a former NCI employee (the “NCI Employee Litigation”). The plaintiff in the NCI Employee Litigation is represented by the same attorney who represented the plaintiff in the ACTF Litigation, and the complaint’s allegations raise issues similar to those in the ACTF Litigation and arise from the same Red Jacket Contract that was at issue in the ACTF Litigation. The Company believes that NCI has meritorious defenses to the claims asserted in the NCI Employee Litigation.
NCI filed its answer to the complaint in the NCI Employee Litigation on March 4, 2013. On April 23, 2013, the Circuit Court of Kanawha County, West Virginia, granted NCI’s motion to transfer and entered an agreed order transferring the NCI Employee Litigation from the Circuit Court of Mingo County to the Circuit Court of Kanawha County.
On November 14, 2013, the Circuit Court of Kanawha County granted NCI’s Motion to Certify Questions of Law to the Supreme Court of Appeals of West Virginia, but on June 17, 2014, the Supreme Court declined to review the submitted questions in the absence of a more developed factual record in the lower court. Proceedings in the Circuit Court of Kanawha County, West Virginia therefore resumed. The Circuit Court has scheduled the trial for April 25-29 and May 2-6, 2016.
On October 14, 2014, NCI filed and served a third party complaint against WVDOH seeking a declaration of rights and obligations of the parties. Specifically, the complaint seeks a determination as to whether NCI is entitled to indemnification for any liability it may incur in the NCI Employee Litigation. The complaint also seeks a declaration that the Red Jacket Contract obligates WVDOH to enter into a supplemental agreement with NCI to reimburse NCI for any additional costs incurred, or to be incurred, as a result of the changes to the Red Jacket Contract arising from the February 26, 2013 order entered against WVDOH in the ACTF Litigation, including without limitation any costs and expenses incurred, or to be incurred, by NCI related to the wage and benefit rates for work on the project, including to the extent any such additional costs, damages, statutory penalties, and/or attorney fees are awarded against NCI in the NCI Employee Litigation. WVDOH moved to dismiss the third party complaint on grounds of sovereign immunity and exclusive jurisdiction of the West Virginia Court of Claims.
On February 20, 2015, the Circuit Court of Kanawha County held a hearing on pending matters, including the WVDOH motion to dismiss the third party complaint filed against it by NCI. The Circuit Court ruled from the bench that it would grant WVDOH’s motion to dismiss NCI’s third party complaint and thereby dismiss WVDOH from this action. A formal written dismissal order is expected to be entered soon. The Company is reviewing this development and evaluating its options.
Fluor Litigation
Alpha Appalachia and certain of its subsidiaries are also parties to a number of lawsuits and other legal proceedings related to certain non-coal businesses (the “Prior Business”) previously conducted by its former affiliate Fluor Corporation. These lawsuits include the Alexander-Pederson-Helig cases in which two of Alpha Appalachia’s subsidiaries, Appalachia Holding Company (“Appalachia Holding”) and DRIH Corporation (“DRIH”), were named defendants along with Fluor.
Under the terms of the Distribution Agreement entered into by Alpha Appalachia and Fluor as of November 30, 2000 in connection with the spin-off of Fluor by Massey, Fluor agreed to indemnify Massey with respect to all such legal proceedings and assumed defense of the proceedings. Consistent with that agreement, in September 2011, Fluor submitted to the court a number of surety bonds covering the full amount of the judgments against Fluor and Alpha Appalachia’s subsidiaries in the Alexander-Pederson-Helig cases. In January 2012, Fluor moved for a reduction in the surety bond amount pending appeal. The Missouri Court of Appeals granted Fluor’s motion in March 2012 and reduced the amount of the surety bonds required to be submitted by the defendants collectively to $150,000, which Fluor submitted on behalf of itself and Alpha Appalachia’s subsidiaries.
In July 2011, certain of these cases alleging personal injury resulted in a jury award in the City of St. Louis Circuit Court in favor of the plaintiffs for $38,500 in compensatory and economic damages and $320,000 in punitive damages (the “Alexander Judgment”). The total aggregate judgment against Alpha Appalachia’s subsidiaries was $118,500. In June 2014, the Missouri Court of Appeals (i) affirmed the jury award of $38,500 in compensatory damages against Fluor, Appalachia Holding and DRIH, jointly and severally, as well as the award of $48,000 in punitive damages against Appalachia Holding and $32,000 against DRIH, and (ii) vacated the award of $240,000 in punitive damages against Fluor and remanded the case for a new trial solely on the amount of punitive damages as to Fluor. In July 2014, the defendants filed with the Missouri Court of Appeals a petition for rehearing by the panel or rehearing en banc and an application to transfer the appeal to the Missouri Supreme Court in the event rehearing by the Court of Appeals were denied.
The Company has recorded an indemnity receivable of $38,500 and has accrued a liability of $38,500, included in prepaid expenses and other current assets and accrued expenses and other current liabilities, respectively, in the Condensed Consolidated Balance Sheet at December 31, 2014.
In connection with Fluor’s sale of the Prior Business to a group of purchasers (the “Rennert Entities”) in 1994, the Rennert Entities agreed to indemnify Fluor and its affiliates for losses and liabilities arising from the Prior Business. In late 2010, the Rennert Entities settled with the plaintiffs in the Alexander-Pederson-Helig cases without indemnifying or obtaining a release for the benefit of Fluor and Alpha Appalachia’s subsidiaries.
In January 2012, the Rennert Entities filed suit against Fluor and two of Alpha Appalachia’s subsidiaries in the United States District Court for the Eastern District of Missouri seeking return of funds previously paid by the Rennert Entities to settle personal injury and property damage claims against Fluor and Alpha Appalachia’s subsidiaries allegedly arising out of the Prior Business and a declaration of non-liability for indemnification with respect to the Alexander-Pederson-Helig cases and any future claims or judgments against Fluor and Alpha Appalachia’s subsidiaries arising out of the Prior Business. Also in January 2012, Fluor filed suit against the Rennert Entities in Missouri state court alleging various breach of contract and tort claims and seeking a declaratory judgment regarding the Rennert Entities’ indemnification obligations to Fluor and Alpha Appalachia’s subsidiaries against claims arising out of the Prior Business. In February 2012, Appalachia Holding and DRIH joined Fluor as plaintiffs in this suit. At the same time, Fluor, Appalachia Holding and DRIH moved to dismiss, or in the alternative, to stay the suit pending in federal court in Missouri in favor of the Missouri state court action. In June 2012, Missouri federal court stayed the case before it in favor of the suit pending in the Missouri state court.
In April 2012, the Rennert entities moved to dismiss the Missouri state court action. In July 2012, the Missouri state court scheduled an expedited hearing on the Rennert entities’ pending motions to dismiss for August 2012. In October 2012, the court denied the Rennert entities’ motions to dismiss each of Fluor’s and Alpha Appalachia’s subsidiaries’ claims except for one claim for contribution, which the court dismissed. All defendants answered in October 2012. Discovery subsequently commenced.
In January 2015, Fluor entered into a settlement agreement with plaintiffs asserting personal injury claims, settling the case on behalf of itself, Appalachia Holding and DRIH. The settlement includes the settlement of the Alexander Judgment and has been approved by the Court. The Company expects that Fluor will continue to indemnify the Alpha entities with respect to any similar cases not covered by the settlement or that are asserted in the future.
Harman Litigation
In December 1997, Wellmore Coal Corporation (“Wellmore”), then a subsidiary of A. T. Massey Coal Company (“A. T. Massey”), which is now a subsidiary of the Company, declared force majeure under its coal supply agreement with Harman Mining Corporation (“Harman”) and reduced the amount of coal to be purchased from Harman. In October 1998, Harman and several entities affiliated with it, as well as their ultimate sole shareholder (together “Harman plaintiffs”), sued A.T. Massey and five of its subsidiaries (the “Massey Defendants”) in the Circuit Court of Boone County, West Virginia, alleging that the Massey Defendants tortiously interfered with Wellmore’s agreement with Harman, causing Harman to go out of business. In August 2002, the jury awarded the plaintiffs $50,000 in compensatory and punitive damages.
In October 2006, the Massey Defendants appealed the case to the Supreme Court of Appeals of West Virginia (“WV Supreme Court”). In November 2007, the WV Supreme Court issued a 3-2 majority opinion reversing the judgment against the Massey Defendants and remanding the case to the Circuit Court of Boone County with directions to enter an order dismissing the case, with prejudice, in its entirety. On motion by the Harman plaintiffs, the WV Supreme Court agreed to rehear the case but, in April 2008, it again reversed the judgment against the Massey Defendants and remanded the case with direction to enter an order dismissing the case, with prejudice, in its entirety.
In July 2008, the Harman plaintiffs petitioned the United States Supreme Court (the “U.S. Supreme Court”) to review the WV Supreme Court’s dismissal of their claims. In December 2008, the U.S. Supreme Court agreed to review the case based on the question of whether a justice of the WV Supreme Court should have recused himself from the appeal. The U.S. Supreme Court found that the justice should have recused himself and ruled in June 2009 that the matter should be reheard by the WV Supreme Court.
The WV Supreme Court heard oral arguments on the matter in September 2009, and in November 2009 reversed the lower court’s decision, ruling that all claims brought in connection with the parties dealings must be brought in Virginia. The Harman plaintiffs subsequently requested that the WV Supreme Court reconsider its decision; the WV Supreme Court denied that request.
In November 2010, Harman plaintiffs re-filed their claims in the Circuit Court of Buchanan County, Virginia, this time solely against A.T. Massey, seeking compensatory damages of approximately $44,000, plus pre- and post-judgment interest and punitive damages. A. T. Massey filed a plea of res judicata, and in December 2011 the Buchanan County Circuit Court granted the plea and dismissed the Harman plaintiffs’ claims. The Harman plaintiffs appealed that decision to the Virginia Supreme Court, and on April 18, 2013, the Virginia Supreme Court reversed the decision of the Buchanan County Circuit Court, finding that res judicata did not bar the Harman plaintiffs’ claims. The matter was remanded to the Buchanan County Circuit Court for further proceedings.
On May 23, 2014, a jury in Buchanan County Circuit Court found for the Harman plaintiffs and awarded them $5,000 in damages, plus prejudgment interest of approximately $1,120. On June 13, 2014, the Harman plaintiffs filed motions seeking a new trial on damages and attorneys’ fees, and A.T. Massey filed a motion to set aside the damages verdict. The Circuit Court has not yet ruled on these motions. On January 7, 2015, the Circuit Court granted the Harman plaintiffs a new trial regarding damages.
Emerald Purported Securities Class Action
On July 13, 2012, a purported class action brought on behalf of a putative class of former Massey stockholders was filed in Boone County, West Virginia Circuit Court. The complaint asserts claims under the Securities Act of 1933, as amended, against the Company and certain of its officers and current and former directors, and generally asserts that the defendants made false statements about the Company’s Emerald mine in its public filings associated with the Massey Acquisition. The plaintiff seeks, among other relief, an award of compensatory damages in an amount to be proven at trial. The plaintiff filed an amended complaint in the Boone County Circuit Court on February 6, 2013. The defendants filed motions to dismiss the amended complaint on March 22, 2013 and March 29, 2013. On January 8, 2015, the Boone County Circuit Court dismissed with prejudice all claims in the plaintiff’s amended complaint. The plaintiffs did not appeal the dismissal.
On April 25, 2014, the named plaintiff in the West Virginia Circuit Court action described above filed a second complaint in Greene County, Pennsylvania, Court of Common Pleas, again asserting claims under the Securities Act of 1933, as amended, against the Company and certain of its officers and current and former directors, and generally asserts that the defendants made false statements about the Company’s Emerald mine in its public filings associated with the Massey Acquisition. The plaintiff seeks, among other relief, an award of compensatory damages in an amount to be proven at trial. By agreement of the parties, the defendants’ time to answer, move or otherwise respond to the Pennsylvania complaint was extended until May 7, 2015.
Other Legal Proceedings
In addition to the matters disclosed above, the Company and its subsidiaries are involved in a number of legal proceedings and governmental examinations incident to its normal business activities. While the Company cannot predict the outcome of these proceedings, the Company does not believe that any liability arising from these matters individually or in the aggregate should have a material impact upon its consolidated cash flows, results of operations or financial condition.

Concentration_of_Credit_Risk_a

Concentration of Credit Risk and Major Customers	12 Months Ended
	Dec. 31, 2014
Risks and Uncertainties [Abstract]
Concentration of Credit Risk and Major Customers	Concentration of Credit Risk and Major Customers
	The Company markets its coal principally to electric utilities in the United States and international and domestic steel producers. Credit is extended based on an evaluation of the customer’s financial condition and collateral is generally not required. Credit losses are provided for in the consolidated financial statements and historically have been minimal. For the years ended December 31, 2014, 2013, and 2012, the Company’s ten largest customers accounted for approximately 45%, 43%, and 42% of total revenues, respectively. Sales to the Company’s largest customer accounted for approximately 8%, 9%, and 9% of total revenues for the years ended December 31, 2014, 2013, and 2012, respectively. Steam coal accounted for approximately 78%, 77%, and 81% of the Company’s coal sales volume during 2014, 2013, and 2012, respectively. Metallurgical coal accounted for approximately 22%, 23%, and 19% of the Company’s coal sales volume during 2014, 2013, and 2012, respectively. Additionally, two of the Company's customers had outstanding balances in excess of 10% of the total accounts receivable balance as of December 31, 2014.

Segment_Information

Segment Information	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Segment Information	Segment Information
	The Company extracts, processes and markets steam and metallurgical coal from surface and deep mines for sale to electric utilities, steel and coke producers, and industrial customers. The Company operates only in the United States with mines in Northern and Central Appalachia and the Powder River Basin. The Company has two reportable segments: Western Coal Operations, which consists of two Powder River Basin surface mines as of December 31, 2014, and Eastern Coal Operations, which consists of 45 underground mines and 13 surface mines in Northern and Central Appalachia as of December 31, 2014, as well as coal brokerage activities.
	In addition to the two reportable segments, the All Other category includes an idled underground mine in Illinois; expenses associated with certain closed mines; Dry Systems Technologies; revenues and royalties from the sale of natural gas; equipment sales and repair operations; terminal services; the leasing of mineral rights; general corporate overhead and corporate assets and liabilities. The Company evaluates the performance of its segments based on EBITDA, which the Company defines as net income (loss) plus interest expense, income tax expense, amortization of acquired intangibles, net, and depreciation, depletion and amortization, less interest income and income tax benefit.
	Segment operating results and capital expenditures for the year ended December 31, 2014 were as follows:
		Eastern			Western			All			Consolidated
		Coal			Coal			Other
		Operations			Operations
	Total revenues	$	3,803,396		$	443,953		$	39,729		$	4,287,078
	Depreciation, depletion and amortization(1)	$	670,520		$	59,591		$	20,665		$	750,776
	Amortization of acquired intangibles, net	$	41,149		$	(2,119	)	$	176		$	39,206
	EBITDA(1)(2)	$	188,337		$	16,053		$	(58,459	)	$	145,931
	Capital expenditures	$	170,063		$	12,562		$	2,413		$	185,038
	Acquisition of mineral rights under federal lease	$	—		$	42,130		$	—		$	42,130
	(1)Amounts for Eastern Coal Operations and Consolidated include certain out of period adjustments recorded related to asset retirement obligations. The adjustments did not impact any other segment. The adjustment recorded related to a decrease to depreciation, depletion and amortization of $13,583 and cost of coal sales of $29,987 and an increase to EBITDA of $29,987. See Note 15 for further details.
	(2) Amounts for Eastern Coal Operations and All Other include asset impairment and restructuring expenses of $15,100 and $9,772, respectively. Additionally, EBITDA for Eastern Coal Operations includes a goodwill impairment charge of $308,651. See Notes 10 and 11 for further information.
	Segment operating results and capital expenditures for the year ended December 31, 2013 were as follows:
		Eastern			Western			All			Consolidated
		Coal			Coal			Other
		Operations			Operations
	Total revenues	$	4,412,334		$	487,324		$	53,850		$	4,953,508
	Depreciation, depletion and amortization	$	780,120		$	54,265		$	30,636		$	865,021
	Amortization of acquired intangibles, net	$	7,916		$	(2,878	)	$	18		$	5,056
	EBITDA(1)	$	(44,223	)	$	90,879		$	(263,556	)	$	(216,900	)
	Capital expenditures	$	207,503		$	5,369		$	2,789		$	215,661
	Acquisition of mineral rights under federal lease	$	—		$	42,130		$	—		$	42,130
	(1) Amounts for Eastern Coal Operations, Western Coal Operations, and and All Other include asset impairment and restructuring expenses of $14,384, ($411), and $23,300 respectively. Additionally, EBITDA for Eastern Coal Operations includes a goodwill impairment charge of $253,102. See Notes 10 and 11 for further information.
	Segment operating results and capital expenditures for the year ended December 31, 2012 were as follows:
		Eastern			Western			All			Consolidated
		Coal			Coal			Other
		Operations			Operations
	Total revenues	$	6,290,289		$	611,329		$	73,266		$	6,974,884
	Depreciation, depletion and amortization	$	949,064		$	62,729		$	25,782		$	1,037,575
	Amortization of acquired intangibles, net	$	(87,875	)	$	13,644		$	3,893		$	(70,338	)
	EBITDA(1)	$	(1,807,515	)	$	65,153		$	(82,771	)	$	(1,825,133	)
	Capital expenditures	$	368,838		$	18,082		$	15,457		$	402,377
	Acquisition of mineral rights under federal lease	$	—		$	95,765		$	—		$	95,765
	(1) Amounts for Eastern Coal Operations, Western Coal Operations, and and All Other include asset impairment and restructuring expenses of $1,033,979, $823, and $34,104 respectively. Additionally, EBITDA for Eastern Coal Operations and Western Coal Operations include goodwill impairment charges of $1,660,218 and $53,308, respectively. See Notes 10 and 11 for further information.
	The following table presents a reconciliation of EBITDA to net loss for the years ended:
		December 31,
		2014			2013			2012
	EBITDA	$	145,931		$	(216,900	)	$	(1,825,133	)
	Interest expense	(288,466		)	(246,588		)	(198,147		)
	Interest income	2,265			3,517			3,373
	Income tax benefit	55,291			216,550			549,996
	Depreciation, depletion and amortization	(750,776		)	(865,021		)	(1,037,575		)
	Amortization of acquired intangibles, net	(39,206		)	(5,056		)	70,338
	Net loss	$	(874,961	)	$	(1,113,498	)	$	(2,437,148	)
	The following table presents total assets and goodwill:
		Total Assets									Goodwill, net
		December 31,			December 31,			December 31,			December 31,			December 31,		December 31,
		2014			2013			2012			2014			2013		2012
	Eastern Coal Operations	$	8,648,678		$	9,566,687		$	10,691,029		$	—		$	308,651	$	561,753
	Western Coal Operations	657,971			645,175			647,292			—			—		—
	All Other	1,429,499			1,587,396			1,751,485			—			—		5,912
	Total	$	10,736,148		$	11,799,258		$	13,089,806		$	—		$	308,651	$	567,665
	The Company sells produced, processed and purchased coal to customers in the United States and in international markets, primarily the Netherlands, Italy, Turkey, United Kingdom, Brazil, and India. Export coal revenues, which include freight and handling revenues, totaled $1,664,557 or approximately 39% of total revenues for the year ended December 31, 2014, $2,151,464 or approximately 43% of total revenues for the year ended December 31, 2013; and $2,930,557 or approximately 42% of total revenues for the year ended December 31, 2012.

Guarantor_and_NonGuarantor_Inf

Guarantor and Non-Guarantor Information	12 Months Ended
	Dec. 31, 2014
Supplemental Guarantor and Non-Guarantor Financial Information [Abstract]
Supplemental Guarantor and Non-Guarantor Financial Information	Guarantor and Non-Guarantor Information
	The Company has issued senior notes and convertible senior notes and may issue new debt securities (the “New Notes”) in the future that are and will be, respectively, fully and unconditionally guaranteed, jointly and severally, on a senior or subordinated, secured or unsecured basis by certain of the Company’s 100% owned subsidiaries (the “New Notes Guarantor Subsidiaries”).
	Presented below are Condensed Consolidating Financial Statements as of December 31, 2014 and 2013 and for the years ended December 31, 2014, 2013, and 2012, respectively, based on the guarantor structure that was put in place in connection with the issuance of its senior notes and convertible senior notes, and would be put in place in the event the Company issues New Notes in the future. The tables below refer to the Company as issuer of the Senior Notes and of any New Notes that may be issued in the future. “Non-Guarantor Subsidiaries” refers, for the tables below, to ANR Receivables Funding, LLC, Gray Hawk Insurance Company, Shannon-Pocahontas Mining Company, Alpha Coal Sales International Limited, Alpha Natural Resources Singapore Private Limited, Alpha Coal India Private Limited, Rockridge Coal Company, Coalsolv, LLC, Alpha Australia Pty. Limited and ANR Second Receivables Funding, LLC, which were not guarantors of the Senior Notes or the Convertible Notes and would not be guarantors of the New Notes. Separate consolidated financial statements and other disclosures concerning the New Notes Guarantor Subsidiaries are not presented because management believes that such information would not be material to holders of any New Notes or related guarantees that may be issued by the Company.
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Balance Sheet
	December 31, 2014
		Parent			Guarantor			Non-Guarantor			Eliminations			Total
		(Issuer)			Subsidiaries			Subsidiaries						Consolidated
	Assets
	Current assets:
	Cash and cash equivalents	$	830		$	738,700		$	1,656		$	—		$	741,186
	Trade accounts receivable, net	—			43,784			270,231			—			314,015
	Inventories, net	—			237,945			—			—			237,945
	Short-term marketable securities	—			405,169			—			—			405,169
	Prepaid expenses and other current assets	—			175,221			2,778			—			177,999
	Total current assets	830			1,600,819			274,665			—			1,876,314
	Property, equipment and mine development costs, net	—			1,425,667			—			—			1,425,667
	Owned and leased mineral rights and land, net	—			6,916,307			—			—			6,916,307
	Other acquired intangibles, net	—			97,169			—			—			97,169
	Other non-current assets	8,142,716			8,363,729			14,329			(16,100,083		)	420,691
	Total assets	$	8,143,546		$	18,403,691		$	288,994		$	(16,100,083	)	$	10,736,148
	Liabilities and Stockholders’ Equity
	Current liabilities:
	Current portion of long-term debt	$	49,752		$	128,499		$	—		$	—		$	178,251
	Trade accounts payable	—			215,972			126			—			216,098
	Accrued expenses and other current liabilities	3,130			611,833			237			—			615,200
	Total current liabilities	52,882			956,304			363			—			1,009,549
	Long-term debt	3,678,449			41,070			—			—			3,719,519
	Pension and postretirement medical benefit obligations	—			1,236,986			—			—			1,236,986
	Asset retirement obligations	—			538,008			—			—			538,008
	Deferred income taxes	—			773,466			—			—			773,466
	Other non-current liabilities	1,425,415			1,630,041			267,195			(2,850,831		)	471,820
	Total liabilities	5,156,746			5,175,875			267,558			(2,850,831		)	7,749,348
	Stockholders’ Equity
	Total stockholders’ equity	2,986,800			13,227,816			21,436			(13,249,252		)	2,986,800
	Total liabilities and stockholders’ equity	$	8,143,546		$	18,403,691		$	288,994		$	(16,100,083	)	$	10,736,148
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Balance Sheet
	December 31, 2013
		Parent						Non-Guarantor			Eliminations			Total
		(Issuer)			Guarantor			Subsidiaries						Consolidated
					Subsidiaries
	Assets
	Current assets:
	Cash and cash equivalents	$	467		$	617,952		$	1,225		$	—		$	619,644
	Trade accounts receivable, net	—			287,655			—			—			287,655
	Inventories, net	—			304,863			—			—			304,863
	Short-term marketable securities	—			337,069			—			—			337,069
	Prepaid expenses and other current assets	—			436,352			2,841			—			439,193
	Total current assets	467			1,983,891			4,066			—			1,988,424
	Property, equipment and mine development costs, net	—			1,798,648			—			—			1,798,648
	Owned and leased mineral rights and land, net	—			7,157,506			—			—			7,157,506
	Goodwill, net	—			308,651			—			—			308,651
	Other acquired intangibles, net	—			158,465			—			—			158,465
	Other non-current assets	8,602,537			8,786,932			13,826			(17,015,731		)	387,564
	Total assets	$	8,603,004		$	20,194,093		$	17,892		$	(17,015,731	)	$	11,799,258
	Liabilities and Stockholders’ Equity
	Current liabilities:
	Current portion of long-term debt	$	6,250		$	22,919		$	—		$	—		$	29,169
	Trade accounts payable	—			234,951			—			—			234,951
	Accrued expenses and other current liabilities	3,130			975,365			200			—			978,695
	Total current liabilities	9,380			1,233,235			200			—			1,242,815
	Long-term debt	3,222,906			175,528			—			—			3,398,434
	Pension and postretirement medical benefit obligations	—			990,124			—			—			990,124
Asset retirement obligations	—			728,575			—			—			728,575
Deferred income taxes	—			901,552			—			—			901,552
Other non-current liabilities	1,298,852			1,764,744			—			(2,597,704		)	465,892
Total liabilities	4,531,138			5,793,758			200			(2,597,704		)	7,727,392
Stockholders’ Equity
Total stockholders’ equity	4,071,866			14,400,335			17,692			(14,418,027		)	4,071,866
Total liabilities and stockholders’ equity	$	8,603,004		$	20,194,093		$	17,892		$	(17,015,731	)	$	11,799,258
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statement of Operations
Year Ended December 31, 2014
	Parent						Non-Guarantor			Eliminations			Total
	(Issuer)			Guarantor			Subsidiaries						Consolidated
				Subsidiaries
Revenues:
Coal revenues	$	—		$	3,724,441		$	—		$	—		$	3,724,441
Freight and handling revenues	—			480,841			—			—			480,841
Other revenues	—			78,431			3,365			—			81,796
Total revenues	—			4,283,713			3,365			—			4,287,078
Costs and expenses:
Cost of coal sales (exclusive of items shown separately below)	—			3,381,075			—			—			3,381,075
Freight and handling costs	—			480,841			—			—			480,841
Other expenses	—			67,412			—			—			67,412
Depreciation, depletion and amortization	—			750,776			—			—			750,776
Amortization of acquired intangibles, net	—			39,206			—			—			39,206
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)	—			150,111			1,995			—			152,106
Asset impairment and restructuring	—			24,872			—			—			24,872
Goodwill impairment	—			308,651			—			—			308,651
Total costs and expenses	—			5,202,944			1,995			—			5,204,939
Income (loss) from operations	—			(919,231		)	1,370			—			(917,861		)
Other income (expense):
Interest expense	(286,703		)	(1,139		)	(624		)	—			(288,466		)
Interest income	—			520			1,745			—			2,265
Gain on sale of marketable equity securities	—			17,883			—			—			17,883
Loss on early extinguishment of debt	(1,630		)	(392		)	—			—			(2,022		)
Gain on exchange of equity method investment	—			256,330			—			—			256,330
Miscellaneous income (expense), net	—			1,770			(151		)	—			1,619
Total other income (expense), net	(288,333		)	274,972			970			—			(12,391		)
Income (loss) before income taxes and equity in earnings of investments in Issuer and Guarantor Subsidiaries	(288,333		)	(644,259		)	2,340			—			(930,252		)
Income tax benefit (expense)	112,450			(56,245		)	(914		)	—			55,291
Equity in earnings of investments in Issuer and Guarantor Subsidiaries	(699,078		)	—			—			699,078			—
Net income (loss)	$	(874,961	)	$	(700,504	)	$	1,426		$	699,078		$	(874,961	)
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statement of Operations
Year Ended December 31, 2013
	Parent						Non-Guarantor			Eliminations			Total
	(Issuer)			Guarantor			Subsidiaries						Consolidated
				Subsidiaries
Revenues:
Coal revenues	$	—		$	4,257,981		$	—		$	—		$	4,257,981
Freight and handling revenues	—			557,846			—			—			557,846
Other revenues	—			132,074			5,607			—			137,681
Total revenues	—			4,947,901			5,607			—			4,953,508
Costs and expenses:
Cost of coal sales (exclusive of items shown separately below)	—			3,980,744			—			—			3,980,744
Freight and handling costs	—			557,846			—			—			557,846
Other expenses	—			165,485			—			—			165,485
Depreciation, depletion and amortization	—			865,021			—			—			865,021
Amortization of acquired intangibles, net	—			5,056			—			—			5,056
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)	—			156,155			2,832			—			158,987
Asset impairment and restructuring	—			37,273			—			—			37,273
Goodwill impairment	—			253,102			—			—			253,102
Total costs and expenses	—			6,020,682			2,832			—			6,023,514
Income from operations	—			(1,072,781		)	2,775			—			(1,070,006		)
Other income (expense):
Interest expense	(232,194		)	(13,213		)	(1,181		)	—			(246,588		)
Interest income	—			3,463			54			—			3,517
Loss on early extinguishment of debt	(30,139		)	(8,967		)	(1,358		)	—			(40,464		)
Miscellaneous income (expense), net	—			23,573			(80		)	—			23,493
Total other expense, net	(262,333		)	4,856			(2,565		)	—			(260,042		)
Loss before income taxes and equity in earnings of investments in Issuer and Guarantor Subsidiaries	(262,333		)	(1,067,925		)	210			—			(1,330,048		)
Income tax benefit (expense)	102,310			114,322			(82		)	—			216,550
Equity in earnings of investments in Issuer and Guarantor Subsidiaries	(953,475		)	—			—			953,475			—
Net income (loss)	$	(1,113,498	)	$	(953,603	)	$	128		$	953,475		$	(1,113,498	)
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statement of Operations
Year Ended December 31, 2012
	Parent						Non-Guarantor			Eliminations			Total
	(Issuer)			Guarantor			Subsidiaries						Consolidated
				Subsidiaries
Revenues:
Coal revenues	$	—		$	6,015,696		$	—		$	—		$	6,015,696
Freight and handling revenues	—			761,928			—			—			761,928
Other revenues	—			184,017			13,243			—			197,260
Total revenues	—			6,961,641			13,243			—			6,974,884
Costs and expenses:
Cost of coal sales (exclusive of items shown separately below)	—			5,004,516			—			—			5,004,516
Freight and handling costs	—			761,928			—			—			761,928
Other expenses	—			45,432			—			—			45,432
Depreciation, depletion and amortization	—			1,037,575			—			—			1,037,575
Amortization of acquired intangibles, net	—			(70,338		)	—			—			(70,338		)
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)	—			205,156			4,632			—			209,788
Asset impairment and restructuring	—			1,068,906			—			—			1,068,906
Goodwill impairment	—			1,713,526			—			—			1,713,526
Total costs and expenses	—			9,766,701			4,632			—			9,771,333
Income (loss) from operations	—			(2,805,060		)	8,611			—			(2,796,449		)
Other income (expense):
Interest expense	(170,111		)	(25,063		)	(2,973		)	—			(198,147		)
Interest income	—			3,347			26			—			3,373
Gain on early extinguishment of debt	—			773			—			—			773
Miscellaneous expense, net	—			3,349			(43		)	—			3,306
Total other expense, net	(170,111		)	(17,594		)	(2,990		)	—			(190,695		)
Income (loss) before income taxes and equity in earnings of investments in Issuer and Guarantor Subsidiaries	(170,111		)	(2,822,654		)	5,621			—			(2,987,144		)
Income tax benefit (expense)	66,343			485,845			(2,192		)	—			549,996
Equity in earnings of investments in Issuer and Guarantor Subsidiaries	(2,333,380		)	—			—			2,333,380			—
Net income (loss)	$	(2,437,148	)	$	(2,336,809	)	$	3,429		$	2,333,380		$	(2,437,148	)
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statements of Comprehensive Income (Loss)
For the Year Ended December 31, 2014
	Parent			Guarantor			Non-Guarantor			Eliminations			Total
	(Issuer)			Subsidiaries			Subsidiaries						Consolidated
Net income (loss)	$	(874,961	)	$	(700,504	)	$	1,426		$	699,078		$	(874,961	)
Total comprehensive income (loss)	$	(1,109,514	)	$	(935,057	)	$	1,426		$	933,631		$	(1,109,514	)
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statements of Comprehensive Income (Loss)
For the Year Ended December 31, 2013
	Parent			Guarantor			Non-Guarantor			Eliminations			Total
	(Issuer)			Subsidiaries			Subsidiaries						Consolidated
Net income (loss)	$	(1,113,498	)	$	(953,603	)	$	128		$	953,475		$	(1,113,498	)
Total comprehensive income (loss)	$	(1,004,048	)	$	(844,153	)	$	128		$	844,025		$	(1,004,048	)
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statements of Comprehensive Income (Loss)
For the Year Ended December 31, 2012
	Parent			Guarantor			Non-Guarantor			Eliminations			Total
	(Issuer)			Subsidiaries			Subsidiaries						Consolidated
Net income (loss)	$	(2,437,148	)	$	(2,336,809	)	$	3,429		$	2,333,380		$	(2,437,148	)
Total comprehensive income (loss)	$	(2,401,916	)	$	(2,301,577	)	$	3,429		$	2,298,148		$	(2,401,916	)
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statement of Cash Flows
Year Ended December 31, 2014
	Parent						Non-Guarantor			Total
	(Issuer)			Guarantor			Subsidiaries			Consolidated
				Subsidiaries
Net cash (used in) provided by operating activities	$	—		$	(284,022	)	$	163		$	(283,859	)
Investing activities:
Capital expenditures	—			(185,038		)	—			(185,038		)
Acquisition of mineral rights under federal lease	—			(42,130		)	—			(42,130		)
Purchases of marketable securities	—			(679,394		)	—			(679,394		)
Sales of marketable securities	—			697,929			—			697,929
Proceeds from sale of property, plant and equipment	—			93,033			—			93,033
Proceeds from the sale of equity method investments, net	—			112,232			—			112,232
Other, net	—			1,717			—			1,717
Net cash used in investing activities	—			(1,651		)	—			(1,651		)
Financing activities:
Proceeds from borrowings on long-term debt	500,000			—			—			500,000
Principal repayments of long-term debt	(27,635		)	(9,919		)	—			(37,554		)
Principal repayments of capital lease obligations	—			(19,475		)	—			(19,475		)
Debt issuance costs and modification costs	(24,634		)	—			(4,304		)	(28,938		)
Common stock repurchases	(1,461		)	—			—			(1,461		)
Other, net	—			(5,520		)	—			(5,520		)
Transactions with affiliates	(445,907		)	441,335			4,572			—
Net cash provided by financing activities	363			406,421			268			407,052
Net increase in cash and cash equivalents	363			120,748			431			121,542
Cash and cash equivalents at beginning of period	467			617,952			1,225			619,644
Cash and cash equivalents at end of period	$	830		$	738,700		$	1,656		$	741,186
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statement of Cash Flows
Year Ended December 31, 2013
	Parent						Non-Guarantor			Total
	(Issuer)			Guarantor			Subsidiaries			Consolidated
				Subsidiaries
Net cash provided by operating activities	$	—		$	108,904		$	114		$	109,018
Investing activities:
Capital expenditures	—			(215,661		)	—			(215,661		)
Acquisition of mineral rights under federal lease	—			(42,130		)	—			(42,130		)
Purchases of marketable securities	—			(900,471		)	—			(900,471		)
Sales of marketable securities	—			857,000			—			857,000
Proceeds from sale of property and equipment	—			10,605			—			10,605
Net cash used in investing activities	—			(290,657		)	—			(290,657		)
Financing activities:
Proceeds from borrowings on long-term debt	1,306,677			—			—			1,306,677
Principal repayments on long-term debt	(762,223		)	(414,109		)	—			(1,176,332		)
Principal repayments of capital lease obligations	—			(16,136		)	—			(16,136		)
Debt issuance and modification costs	(36,659		)	—			—			(36,659		)
Common stock repurchases	(1,435		)	—			—			(1,435		)
Other, net	—			(5,555		)	—			(5,555		)
Transactions with affiliates	(506,170		)	505,843			327			—
Net cash provided by financing activities	190			70,043			327			70,560
Net (decrease) increase in cash and cash equivalents	190			(111,710		)	441			(111,079		)
Cash and cash equivalents at beginning of period	277			729,662			784			730,723
Cash and cash equivalents at end of period	$	467		$	617,952		$	1,225		$	619,644
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statement of Cash Flows
Year Ended December 31, 2012
	Parent						Non-Guarantor			Total
	(Issuer)			Guarantor			Subsidiaries			Consolidated
				Subsidiaries
Net cash (used in) provided by operating activities	$	—		$	518,367		$	52		$	518,419
Investing activities:
Capital expenditures	—			(402,377		)	—			(402,377		)
Acquisition of mineral rights under federal lease	—			(95,765		)	—			(95,765		)
Purchases of marketable securities	—			(555,096		)	—			(555,096		)
Sales of marketable securities	—			352,112			—			352,112
Purchase of equity method investment	—			(10,100		)	—			(10,100		)
Proceeds from sale of property, plant and equipment	—			38,250			—			38,250
Net cash used in investing activities	—			(672,976		)	—			(672,976		)
Financing activities:
Proceeds from borrowings on long-term debt	494,795			—			—			494,795
Principal repayments on long-term debt	(45,000		)	(115,157		)	—			(160,157		)
Principal repayments of capital lease obligations	—			(6,490		)	—			(6,490		)
Debt issuance and modification costs	(15,767		)	—			(594		)	(16,361		)
Common stock repurchases	(7,507		)	—			—			(7,507		)
Other, net	176			(5,058		)	—			(4,882		)
Transactions with affiliates	(427,033		)	426,703			330			—
Net cash (used in) provided by financing activities	(336		)	299,998			(264		)	299,398
Net increase (decrease) in cash and cash equivalents	(336		)	145,389			(212		)	144,841
Cash and cash equivalents at beginning of period	613			584,273			996			585,882
Cash and cash equivalents at end of period	$	277		$	729,662		$	784		$	730,723

Quarterly_Financial_Informatio

Quarterly Financial Information (Unaudited)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Information (Unaudited)	Quarterly Financial Information (Unaudited)
		Year Ended December 31, 2014
		First			Second			Third			Fourth
		Quarter			Quarter			Quarter			Quarter(2)
	Total revenues	$	1,111,773		$	1,054,098		$	1,050,592		$	1,070,615
	Net loss (1) (2)	$	(55,698	)	$	(512,627	)	$	(184,975	)	$	(121,661	)
	Basic loss per share	$	(0.25	)	$	(2.32	)	$	(0.84	)	$	(0.55	)
	Diluted loss per share	$	(0.25	)	$	(2.32	)	$	(0.84	)	$	(0.55	)
	(1)	Net loss includes pretax gains on disposals of equity method investments of $250,331 and $5,999 in the first and fourth quarters of 2014, respectively, and pretax asset impairment and restructuring charges of $9,499, $2,590, $11,544 and $1,239 in the first, second, third and fourth quarters of 2014, respectively. Net loss also includes a goodwill impairment charge of $308,651 in the second quarter of 2014.
	(2)	Net loss in the fourth quarter includes certain out of period adjustments for asset retirement obligations related to the first three quarters of 2014 ($6,096) and for the years ended December 31, 2013 and 2012 ($43,570), which decreased net loss by $49,666. These adjustments resulted in a decrease to basic and diluted loss per share of $0.22. See Note 15 for further details.
		Year Ended December 31, 2013
		First			Second Quarter			Third			Fourth
		Quarter						Quarter			Quarter
	Total revenues	$	1,333,591		$	1,335,123		$	1,191,094		$	1,093,700
	Net loss (1)	$	(110,788	)	$	(185,681	)	$	(458,241	)	$	(358,788	)
	Basic loss per share	$	(0.50	)	$	(0.84	)	$	(2.07	)	$	(1.62	)
	Diluted loss per share	$	(0.50	)	$	(0.84	)	$	(2.07	)	$	(1.62	)
	(1)	Net loss includes asset impairment and restructuring charges of $11,076, $11,265, $2,017 and $12,915 in the first, second, third and fourth quarters of 2013, respectively. Net loss also includes goodwill impairment charges of $253,102 in the third quarter of 2013.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Consolidation, Policy [Policy Text Block]	Basis of Presentation
	The consolidated financial statements include Alpha and its majority owned and controlled subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates
	The Company’s consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The preparation of the Company’s consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include inventories; mineral reserves; allowance for non-recoupable advanced mining royalties; asset impairments; reclamation obligations; pensions, postemployment, postretirement medical and other employee benefit obligations; useful lives for depreciation, depletion, and amortization; reserves for workers’ compensation and black lung claims; current and deferred income taxes; reserves for contingencies and litigation; and fair value of financial instruments. Estimates are based on facts and circumstances believed to be reasonable at the time; however, actual results could differ from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents
	Cash and cash equivalents consist of cash held with reputable depository institutions and highly liquid, short-term investments with original maturities of three months or less. Cash and cash equivalents are stated at cost, which approximates fair market value. The Company’s cash equivalents consist of money market funds that are maintained in highly rated funds at December 31, 2014.
Marketable Securities	Marketable Securities
	The Company classifies its marketable securities as trading or available-for-sale. These securities are recorded initially at cost and adjusted to fair value at each reporting date. Unrealized gains and losses resulting from fair value adjustments to available-for-sale securities are classified as a separate component of stockholders’ equity. Unrealized gains and losses resulting from fair value adjustments to trading securities are recorded in current period earnings or loss. Realized gains and losses on available-for-sale securities are computed using the specific identification method. Marketable securities with maturities of one year or less are reported in short-term marketable securities. Marketable securities with maturities of greater than one year are reported in other non-current assets. See Note 7 for further disclosures related to marketable securities.
Trade Accounts Receivable and Allowance for Doubtful Accounts	Trade Accounts Receivable and Allowance for Doubtful Accounts
	Trade accounts receivable are recorded at the invoiced amount and do not bear interest. The allowance for doubtful accounts is the Company’s best estimate of the amount of probable credit losses in the Company’s existing accounts receivable. The Company establishes provisions for losses on accounts receivable when it is probable that all or part of the outstanding balance will not be collected. The Company regularly reviews its accounts receivable balances and establishes or adjusts the allowance as necessary primarily using the specific identification method. The allowance for doubtful accounts was $5,701 and $6,206 at December 31, 2014 and 2013, respectively. Account balances are written off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote.
Inventories	Inventories
	Coal inventories are stated at the lower of average cost or market. The cost of coal inventories is determined based on average cost of production, which includes all costs incurred to extract, transport and process the coal. Market represents the estimated replacement cost, subject to a floor and ceiling, which considers the future sales price of the product as well as remaining estimated preparation and selling costs. Coal is reported as inventory at the point in time the coal is extracted from the mine.
	Material and supplies inventories are valued at average cost, less an allowance for obsolete and surplus items.
Deferred Longwall Move Expenses	Deferred Longwall Move Expenses
	The Company defers the direct costs, including labor and supplies, associated with moving longwall equipment and the related equipment refurbishment costs in prepaid expenses and other current assets. These deferred costs are amortized on a units-of-production basis into cost of coal sales over the life of the subsequent panel of coal mined by the longwall equipment. See Note 8 for further disclosures related to deferred longwall move expenses.
Advanced Mining Royalties	Advanced Mining Royalties
	Lease rights to coal reserves are often acquired in exchange for royalty payments. Advance mining royalties are advance payments made to lessors under terms of mineral lease agreements that are recoupable against future production royalties. These advance payments are deferred and charged to operations as the coal reserves are mined. The Company regularly reviews recoverability of advance mining royalties and establishes or adjusts the allowance for advance mining royalties as necessary using the specific identification method. Advance royalty balances are generally charged off against the allowance when they are no longer recoupable.
	The changes in the allowance for advance mining royalties were as follows:
	Balance at December 31, 2011	$	20,373
	Provision for non-recoupable advance mining royalties	8,913
	Write-offs of advance mining royalties	(1,484		)
	Balance at December 31, 2012	27,802
	Provision for non-recoupable advance mining royalties	3,425
	Write-offs of advance mining royalties	(3,883		)
	Balance at December 31, 2013	27,344
	Provision for non-recoupable advance mining royalties	12,767
	Write-offs of advance mining royalties	(6,339		)
	Balance at December 31, 2014	$	33,772
Property, Equipment and Mine Development Costs	Property, Equipment and Mine Development Costs
	Costs for mine development incurred to expand capacity of operating mines or to develop new mines are capitalized and charged to operations on the units-of-production method over the estimated proven and probable reserve tons directly benefiting from the capital expenditures. Mine development costs include costs incurred for site preparation and development of the mines during the development stage less any incidental revenue generated during the development stage. Mobile mining equipment and other fixed assets are stated at cost and depreciated on a straight-line basis over estimated useful lives ranging from one to 20 years. Leasehold improvements are amortized using the straight-line method, over the shorter of the estimated useful lives or term of the lease. Major repairs and betterments that significantly extend original useful lives or improve productivity are capitalized and depreciated over the period benefited. Maintenance and repairs are expensed as incurred. When equipment is retired or disposed, the related cost and accumulated depreciation are removed from the respective accounts and any profit or loss on disposal is recognized in cost of coal sales.
Owned and Leased Mineral Rights and Land	Owned and Leased Mineral Rights and Land
	Costs to obtain owned and leased mineral rights are capitalized and amortized to operations as depletion expense using the units-of-production method. Only proven and probable reserves are included in the depletion base. Depletion expense is included in depreciation, depletion and amortization on the accompanying Consolidated Statements of Operations and was $230,740, $266,642, and $325,999 for the years ended December 31, 2014, 2013, and 2012, respectively.
Acquired Intangibles	Acquired Intangibles
	Application of acquisition accounting resulted in the recognition of assets for above market-priced coal supply and transportation agreements and liabilities for below market-priced coal supply agreements on the date of the acquisitions. The coal supply and transportation agreements were valued based on the present value of the difference between the expected net contractual cash flows based on the stated contract terms, and the estimated net contractual cash flows derived from applying forward market prices at the acquisition dates for new contracts of similar terms and conditions. The coal supply and transportation agreement assets and liabilities are being amortized over the actual amount of tons shipped under each contract. Coal supply and transportation agreement assets are reported in other acquired intangibles and coal supply agreement liabilities are reported in other non-current liabilities in the Consolidated Balance Sheets.
	In addition, the application of acquisition accounting also resulted in the Company recording intangible assets related to mining permits and covenants not-to-compete, which are reported in other acquired intangibles in the Consolidated Balance Sheets. Amortization of other acquired intangible assets was $61,295, $71,867, and $113,750 of expense and amortization of coal supply agreement liabilities was a credit to expense of ($22,089), ($66,811), and ($184,088), equating to a net expense (credit) of $39,206, $5,056 and ($70,338) for the years ended December 31, 2014, 2013 and 2012, respectively, which is reported as amortization of acquired intangibles, net in the Consolidated Statements of Operations. Future net amortization expense related to acquired intangibles is expected to be as follows:
	2015	$	32,304
	2016	24,522
	2017	5,353
	2018	(357		)
	2019	(243		)
	Thereafter	3,432
	Total net future amortization expense	$	65,011
Asset Impairment and Disposal of Long-Lived Assets	Asset Impairment and Disposal of Long-Lived Assets
	Long-lived assets, such as property, equipment, mine development costs, owned and leased mineral rights and purchased intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset groups may not be recoverable. Recoverability of assets or asset groups to be held and used is measured by a comparison of the carrying amount of an asset or asset group to the estimated undiscounted future cash flows expected to be generated by the asset or asset group. If the carrying amount of an asset or asset group exceeds its estimated future cash flows, an impairment charge is recognized equal to the amount by which the carrying amount of the asset or asset group exceeds the fair value of the asset or asset group. Assets to be disposed would separately be presented in the balance sheet and reported at the lower of the carrying amount or fair value less costs to sell, and would no longer be depreciated. The assets and liabilities of a disposal group classified as held for sale would be presented separately in the Consolidated Balance Sheets. See Note 10 for further disclosures related to asset impairments.
Goodwill	Goodwill
	Goodwill represents the excess of the purchase price over the fair value of the net identifiable tangible and intangible assets of acquired companies. Goodwill is not amortized; instead, it is tested for impairment annually or more frequently if indicators of impairment exist. The Company performs its goodwill impairment testing as of October 31 of each year or sooner if indicators of impairment are present. During 2014, 2013 and 2012, the Company performed interim goodwill impairment tests as of June 1, 2014, February 28, 2014, August 1, 2013 and June 1, 2012.
	The Company first assesses goodwill on a qualitative basis. If the qualitative assessment indicates that an impairment potentially exists, then the Company tests its goodwill for impairment using a fair value approach at the reporting unit level in two steps. Step one compares the fair value of each reporting unit to its carrying amount. If step one indicates that the carrying value of a reporting unit exceeds its fair value, the second step is performed to measure the amount of impairment, if any. Goodwill impairment exists when the estimated implied fair value of goodwill is less than its carrying value. See Note 11 for further disclosures related to goodwill.
Asset Retirement Obligations	Asset Retirement Obligations
	Minimum standards for mine reclamation have been established by various regulatory agencies and dictate the reclamation requirements at the Company’s operations. The Company’s asset retirement obligations consist principally of costs to reclaim acreage disturbed at surface operations, estimated costs to reclaim support acreage, treat mine water discharge and perform other related functions at underground mines. The Company records these reclamation obligations at fair value in the period in which the legal obligation associated with the retirement of the long-lived asset is incurred. Changes to the liability at operations that are not currently being reclaimed are offset by increasing or decreasing the carrying amount of the related long-lived asset. Changes to the liability at operations that are currently being reclaimed are recorded to cost of coal sales. Over time, the liability is accreted and any capitalized cost is depreciated over the useful life of the related asset. To settle the liability, the obligation is paid, and to the extent there is a difference between the liability and the amount of cash paid, a gain or loss upon settlement is recorded. The Company annually reviews its estimated future cash flows for its asset retirement obligations. See Note 15 for further disclosures related to asset retirement obligations.
Income Taxes	Income Taxes
	The Company recognizes deferred tax assets and liabilities using enacted tax rates for the effect of temporary differences between the book and tax basis of recorded assets and liabilities. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that some portion or all of the deferred tax asset will not be realized. In evaluating our ability to recover our deferred tax assets within the jurisdiction in which they arise, we consider all available positive and negative evidence, including the scheduled reversals of deferred tax liabilities, projected future taxable income, taxable income available via carryback to prior years, tax planning strategies, and results of recent operations. Due to the significant negative evidence of cumulative losses in recent years, the Company is unable to utilize estimates of future earnings to support the realization of its deferred tax assets. Therefore, the company is currently relying primarily on income resulting from expected future deferred tax liability reversals, along with carryback opportunities and prudent tax strategies to support the realization of deferred tax assets. If deferred tax assets increase relative to our deferred tax liabilities or circumstances change regarding the reversal patterns of existing deferred balances, the Company would be required to establish additional valuation allowances. See Note 19 for further disclosures related to income taxes.
Revenue Recognition	Revenue Recognition
	The Company earns revenues primarily through the sale of coal, but also earns other revenues from sales of parts, equipment, filters, rebuild and refurbishment services, sales of natural gas and intercontinental commodity transportation services. With the exception of intercontinental commodity transportation services revenue, the Company recognizes revenue using the following general revenue recognition criteria: 1) persuasive evidence of an arrangement exists; 2) delivery has occurred or services have been rendered; 3) the price to the buyer is fixed or determinable; and 4) collectability is reasonably assured. Revenue from intercontinental commodity transportation services is recognized on a ratable basis over the period of time in which transportation services are provided.
	Delivery on our coal sales is determined to be complete for revenue recognition purposes when title and risk of loss has passed to the customer in accordance with stated contractual terms and there are no other future obligations related to the shipment. For domestic shipments, title and risk of loss generally passes as the coal is loaded into transport carriers for delivery to the customer. For international shipments, title generally passes at the time coal is loaded onto the shipping vessel.
	Freight and handling costs paid to third-party carriers and invoiced to coal customers are recorded as freight and handling costs and freight and handling revenues, respectively.
Deferred Financing Costs	Deferred Financing Costs
	The costs to obtain new debt financing or amend existing financing agreements are generally deferred and amortized to interest expense over the life of the related indebtedness or credit facility using the effective interest method. Unamortized deferred financing costs are included in other non-current assets in the Consolidated Balance Sheets.
Workers' Compensation and Pneumoconiosis (Black Lung) Benefits	Workers’ Compensation and Pneumoconiosis (Black Lung) Benefits
	Workers’ Compensation
	The Company is self-insured for workers’ compensation claims at certain of its operations and is covered by third-party insurance providers at other locations. The liabilities for workers’ compensation claims that are self-insured by the Company are estimates of the ultimate losses incurred based on the Company’s experience, and include a provision for incurred but not reported losses. Adjustments to the probable ultimate liabilities are made annually based on an actuarial study and adjustments to the liability are recorded based on the results of this study. These obligations are included in the Consolidated Balance Sheets as accrued expenses and other current liabilities and other non-current liabilities. See Note 20 for further disclosures related to workers’ compensation liabilities.
	Black Lung Benefits
	The Company is required by federal and state statutes to provide benefits to employees for awards related to black lung. The Company is self-insured at certain locations and covered by a third party insurance provider at other locations. Charges are made to operations for self-insured black lung claims, as determined by an independent actuary at the present value of the actuarially computed liability for such benefits over the employee’s applicable term of service. The Company recognizes in its balance sheet the amount of the Company’s unfunded Accumulated Benefit Obligation (“ABO”) at the end of the year. Amounts recognized in accumulated other comprehensive income (loss) are adjusted out of accumulated other comprehensive income (loss) when they are subsequently recognized as components of net periodic benefit cost. See Note 20 for further disclosures related to black lung benefits.
Pension and Other Postretirement Benefits	Pension and Other Postretirement Benefits
	The Company is required to recognize the overfunded or underfunded status of a defined benefit pension plan as an asset or liability in its Consolidated Balance Sheets and to recognize changes in that funded status in the year in which the changes occur through other comprehensive income (loss). The Company is required to measure plan assets and benefit obligations as of the date of the Company’s fiscal year-end balance sheet and provide the required disclosures as of the end of each fiscal year.
	The Company accounts for health care benefits provided for current and certain retired employees and their dependents by accruing the cost of such benefits over the service lives of employees. Unrecognized actuarial gains and losses are amortized over the estimated average remaining service period for active employees and over the estimated average remaining life for retirees. The Company recognizes in its Consolidated Balance Sheets the amount of the Company’s unfunded Accumulated Postretirement Benefit Obligation (“APBO”) at the end of the year. Amounts recognized in accumulated other comprehensive income (loss) are adjusted out of accumulated other comprehensive income (loss) when they are subsequently recognized as components of net periodic benefit cost.
	See Note 20 for further disclosures related to pension and other postretirement benefits.
Earnings Per Share	Earnings Per Share
	Basic earnings per share is computed by dividing net income by the weighted-average number of outstanding common shares for the period. Diluted earnings per share reflects the potential dilution that could occur if instruments that may require the issuance of common shares in the future were settled and the underlying common shares were issued. Diluted earnings per share is computed by increasing the weighted-average number of outstanding common shares computed in basic earnings per share to include the additional common shares that would be outstanding after issuance and adjusting net income for changes that would result from the issuance. Only those securities that are dilutive are included in the calculation. See Note 5 for further disclosures related to earnings per share.
Stock-Based Compensation	Stock-Based Compensation
	The Company recognizes expense for stock-based compensation awards based on the estimated grant-date fair value. For all grants, the amount of compensation expense to be recognized is adjusted for an estimated forfeiture rate which is based in part on historical data and other relevant factors. Compensation expense for awards with cliff vesting provisions is recognized on a straight-line basis from the measurement date through the vesting date. Compensation expense for awards with graded vesting provisions is recognized using the accelerated attribution method. See Note 21 for further disclosures related to stock-based compensation arrangements.
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities
	Derivative financial instruments are recognized as either assets or liabilities in the Consolidated Balance Sheets and measured at fair value. On the date a derivative instrument is entered into, the Company may designate a qualifying derivative instrument as a hedge of the variability of cash flows to be received or paid related to a recognized asset or liability or forecasted transaction (cash flow hedge). The Company formally documents all relationships between hedging instruments and hedged items, as well as its risk-management objective and strategy for undertaking various hedge transactions. This process includes linking all derivatives that are designated as cash flow hedges to specific firm commitments or forecasted transactions. The Company also formally assesses both at the hedge’s inception and on an ongoing basis, whether the derivatives that are used in hedging transactions are highly effective in offsetting changes in cash flows of the related hedged items. When it is determined that a derivative is not highly effective as a hedge or that it has ceased to be a highly effective hedge, the Company discontinues hedge accounting prospectively and records all future changes in fair value in current period earnings or losses.
	For derivative instruments that have not been designated as cash flow hedges, changes in fair value are recorded in current period earnings or losses. For derivative instruments that have been designated as cash flow hedges, the effective portion of the changes in fair value are recorded in accumulated other comprehensive income (loss) and any portion that is ineffective is recorded in current period earnings or losses. Amounts recorded in accumulated other comprehensive income (loss) are reclassified to earnings or losses in the period the underlying hedged transaction affects earnings or when the underlying hedged transaction is probable of not occurring. See Note 18 for further disclosures related to derivative financial instruments and hedging activities.
Equity-Method Investments	Equity Method Investments
	Investments in unconsolidated affiliates that the Company has the ability to exercise significant influence over, but not control, the affiliate’s operating activities are accounted for under the equity method of accounting. Under the equity method of accounting, the Company records its proportionate share of the entity’s net income or loss at each reporting period in the Consolidated Statements of Operations in miscellaneous income, net, with a corresponding entry to increase or decrease the carrying value of the investment.
New Accounting Pronouncements Adopted	New Accounting Pronouncements
	On April 10, 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity (“ASU 2014-08”), which changes the criteria for reporting discontinued operations and requires additional disclosures about discontinued operations. The standard requires that an entity report as a discontinued operation only a disposal that represents a strategic shift in operations that has a major effect on its operations and financial results. ASU 2014-08 is effective prospectively for new disposals that occur within annual periods beginning on or after December 15, 2014. Early adoption is permitted and the Company adopted ASU 2014-08 during the year ended December 31, 2014. Adoption of the standard did not have a material impact on the Company's results of operations.
	On May 28, 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”), which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. ASU 2014-09 will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for the Company on January 1, 2017. Early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company has not yet selected a transition method and is still evaluating the effect of the standard on its ongoing financial reporting.
	On June 19, 2014, the FASB issued ASU 2014-12, Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period (“ASU 2014-12”). The standard requires a reporting entity to treat a performance target that affects vesting and that could be achieved after the requisite service
	period as a performance condition. ASU 2014-12 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2015. Early adoption is permitted and the Company adopted ASU 2014-12 during the year ended December 31, 2014. Adoption of the standard did not have a material impact on the Company's results of operations.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Schedule of changes in the allowance for advance mining royalties	The changes in the allowance for advance mining royalties were as follows:
	Balance at December 31, 2011	$	20,373
	Provision for non-recoupable advance mining royalties	8,913
	Write-offs of advance mining royalties	(1,484		)
	Balance at December 31, 2012	27,802
	Provision for non-recoupable advance mining royalties	3,425
	Write-offs of advance mining royalties	(3,883		)
	Balance at December 31, 2013	27,344
	Provision for non-recoupable advance mining royalties	12,767
	Write-offs of advance mining royalties	(6,339		)
	Balance at December 31, 2014	$	33,772
Schedule of Future net amortization expense related to intangibles	Future net amortization expense related to acquired intangibles is expected to be as follows:
	2015	$	32,304
	2016	24,522
	2017	5,353
	2018	(357		)
	2019	(243		)
	Thereafter	3,432
	Total net future amortization expense	$	65,011

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2014
Accumulated Other Comprehensive Income [Abstract]
Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss)
	The following tables summarize the changes to accumulated other comprehensive income (loss) during the years ended December 31, 2014, 2013, and 2012:
		Balance December 31, 2013			Other comprehensive			Amounts reclassified			Balance
					income (loss) before reclassifications			from accumulated other comprehensive income (loss)			31-Dec-14
	Employee benefit costs	$	(59,102	)	$	(230,708	)	$	(1,308	)	$	(291,118	)
	Cash flow hedges	1,941			—			(2,341		)	(400		)
	Available-for-sale marketable securities	13			10,587			(10,783		)	(183		)
		$	(57,148	)	$	(220,121	)	$	(14,432	)	$	(291,701	)
		Balance December 31, 2012			Other comprehensive			Amounts reclassified			Balance
					income (loss) before reclassifications			from accumulated other comprehensive income (loss)			31-Dec-13
	Employee benefit costs	$	(171,394	)	$	111,960		$	332		$	(59,102	)
	Cash flow hedges	4,755			(971		)	(1,843		)	1,941
	Available-for-sale marketable securities	41			(74		)	46			13
		$	(166,598	)	$	110,915		$	(1,465	)	$	(57,148	)
		Balance December 31, 2011			Other comprehensive			Amounts reclassified			Balance
					income (loss) before reclassifications			from accumulated other comprehensive income (loss)			31-Dec-12
	Employee benefit costs	$	(203,229	)	$	27,433		$	4,402		$	(171,394	)
	Cash flow hedges	1,333			13,812			(10,390		)	4,755
	Available-for-sale marketable securities	66			309			(334		)	41
		$	(201,830	)	$	41,554		$	(6,322	)	$	(166,598	)
	The following table summarizes the amounts reclassified from accumulated other comprehensive income (loss) and the Consolidated Statement of Operations line items affected by the reclassification during the years ended December 31, 2014, 2013, and 2012:
	Details about accumulated other comprehensive income (loss) components	Amounts reclassified from accumulated other comprehensive income (loss)									Affected line item in the Consolidated Statements of Operations
		Year Ended December 31,
		2014			2013			2012
	Employee benefit costs:
	Amortization of actuarial loss	$	258		$	4,561		$	6,493		(1)
	Amortization of prior service credit	(4,477		)	(3,819		)	(641		)	(1)
	Other	2,151			(212		)	1,207			(1)
	Total before income tax	(2,068		)	530			7,059
	Income tax expense (benefit)	760			(198		)	(2,657		)	Income tax benefit
	Total, net of income tax	$	(1,308	)	$	332		$	4,402
	Cash flow hedges:
	Commodity swaps-coal	$	(4,189	)	$	(4,111	)	$	(1,865	)	Coal revenues
	Commodity swaps-diesel fuel	379			2,777			(10,256		)	Cost of coal sales
	Commodity swaps-natural gas	—			(1,865		)	(4,484		)	Other revenues
	Commodity options-natural gas	—			112			—			Other revenues
	Total before income tax	(3,810		)	(3,087		)	(16,605		)
	Income tax benefit	1,469			1,244			6,215			Income tax benefit
	Total, net of income tax	$	(2,341	)	$	(1,843	)	$	(10,390	)
	Available-for-sale marketable securities:
	Realized gains (losses)	$	(17,882	)	$	76		$	(534	)	Gain on sales of marketable equity securities (2014), Interest income (2013 and 2012)
	Income tax expense (benefit)	7,099			(30		)	200			Income tax benefit
	Total, net of income tax	$	(10,783	)	$	46		$	(334	)
	(1) These accumulated other comprehensive income (loss) components are included in the computation of net periodic benefit costs for pension, other postretirement benefit plans and black lung. See Note 20.
Schedule of Accumulated Other Comprehensive Income (Loss)	The following tables summarize the changes to accumulated other comprehensive income (loss) during the years ended December 31, 2014, 2013, and 2012:
		Balance December 31, 2013			Other comprehensive			Amounts reclassified			Balance
					income (loss) before reclassifications			from accumulated other comprehensive income (loss)			31-Dec-14
	Employee benefit costs	$	(59,102	)	$	(230,708	)	$	(1,308	)	$	(291,118	)
	Cash flow hedges	1,941			—			(2,341		)	(400		)
	Available-for-sale marketable securities	13			10,587			(10,783		)	(183		)
		$	(57,148	)	$	(220,121	)	$	(14,432	)	$	(291,701	)
		Balance December 31, 2012			Other comprehensive			Amounts reclassified			Balance
					income (loss) before reclassifications			from accumulated other comprehensive income (loss)			31-Dec-13
	Employee benefit costs	$	(171,394	)	$	111,960		$	332		$	(59,102	)
	Cash flow hedges	4,755			(971		)	(1,843		)	1,941
	Available-for-sale marketable securities	41			(74		)	46			13
		$	(166,598	)	$	110,915		$	(1,465	)	$	(57,148	)
Reclassification out of Accumulated Other Comprehensive Income	The following table summarizes the amounts reclassified from accumulated other comprehensive income (loss) and the Consolidated Statement of Operations line items affected by the reclassification during the years ended December 31, 2014, 2013, and 2012:
	Details about accumulated other comprehensive income (loss) components	Amounts reclassified from accumulated other comprehensive income (loss)									Affected line item in the Consolidated Statements of Operations
		Year Ended December 31,
		2014			2013			2012
	Employee benefit costs:
	Amortization of actuarial loss	$	258		$	4,561		$	6,493		(1)
	Amortization of prior service credit	(4,477		)	(3,819		)	(641		)	(1)
	Other	2,151			(212		)	1,207			(1)
	Total before income tax	(2,068		)	530			7,059
	Income tax expense (benefit)	760			(198		)	(2,657		)	Income tax benefit
	Total, net of income tax	$	(1,308	)	$	332		$	4,402
	Cash flow hedges:
	Commodity swaps-coal	$	(4,189	)	$	(4,111	)	$	(1,865	)	Coal revenues
	Commodity swaps-diesel fuel	379			2,777			(10,256		)	Cost of coal sales
	Commodity swaps-natural gas	—			(1,865		)	(4,484		)	Other revenues
	Commodity options-natural gas	—			112			—			Other revenues
	Total before income tax	(3,810		)	(3,087		)	(16,605		)
	Income tax benefit	1,469			1,244			6,215			Income tax benefit
	Total, net of income tax	$	(2,341	)	$	(1,843	)	$	(10,390	)
	Available-for-sale marketable securities:
	Realized gains (losses)	$	(17,882	)	$	76		$	(534	)	Gain on sales of marketable equity securities (2014), Interest income (2013 and 2012)
	Income tax expense (benefit)	7,099			(30		)	200			Income tax benefit
	Total, net of income tax	$	(10,783	)	$	46		$	(334	)
	(1) These accumulated other comprehensive income (loss) components are included in the computation of net periodic benefit costs for pension, other postretirement benefit plans and black lung. See Note 20.

Inventories_net_Tables

Inventories, net (Tables)	12 Months Ended
	Dec. 31, 2014
Inventory, Net [Abstract]
Schedule of inventories, net	Inventories, net consisted of the following:
		December 31,
		2014		2013
	Raw coal	$	38,301	$	39,830
	Saleable coal	121,590		171,240
	Materials, supplies and other, net	78,054		93,793
	Total inventories, net	$	237,945	$	304,863

Marketable_Securities_Tables

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2014										Dec. 31, 2013
Investments, Debt and Equity Securities [Abstract]
Schedule of short-term marketable securities
		December 31, 2014										31-Dec-13
				Unrealized										Unrealized
		Cost		Gain		Loss			Fair value			Cost		Gain		Loss			Fair value
	Short-term marketable securities:										Short-term marketable securities:
	U.S. treasury and agency securities (a)	$	80,087	$	13	$	(7	)	$	80,093	U.S. treasury and agency securities (a)	$	81,484	$	17	$	(4	)	$	81,497
	Corporate debt securities (a)	325,202		5		(131		)	325,076		Corporate debt securities (a)	255,567		49		(44		)	255,572
	Total short-term marketable securities	$	405,289	$	18	$	(138	)	$	405,169	Total short-term marketable securities	$	337,051	$	66	$	(48	)	$	337,069
Schedule of Available-for-sale Securities Long-Term Portion [Table Text Block]
		December 31, 2014										December 31, 2013
				Unrealized										Unrealized
		Cost		Gain		Loss			Fair value			Cost		Gain		Loss			Fair value
	Long-term marketable securities:										Long-term marketable securities:
	Corporate equity securities (a)	$	127,001	$	—	$	(181	)	$	126,820	Money market and mutual funds held in rabbi trust (b)	$	7,261	$	3,637	$	(1,568	)	$	9,330
	Money market and mutual funds held in rabbi trust (b)	7,433		4,661		(1,987		)	10,107
	Total long-term securities	$	134,434	$	4,661	$	(2,168	)	$	136,927

Prepaid_Expenses_and_Other_Cur1

Prepaid Expenses and Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Prepaid Expense and Other Assets, Current [Abstract]
Disclosure of prepaid expenses and other current assets	Prepaid expenses and other current assets consisted of the following:
		December 31,
		2014		2013
	Prepaid insurance	$	11,445	$	12,273
	Insurance and indemnification receivables (1)	41,283		195,228
	Notes and other receivables	6,771		10,381
	Deferred income taxes - current	54,451		118,757
	Deferred long wall move expenses	9,309		10,766
	Refundable income taxes	13,532		19,708
	Prepaid freight	20,417		26,445
	Deposits	8,834		13,671
	Other prepaid expenses	11,957		31,964
	Total prepaid expenses and other current assets	$	177,999	$	439,193
	(1)	See Note 13.

Property_Equipment_and_Mine_De1

Property, Equipment and Mine Development Costs (Tables)	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Schedule of property, equipment and development costs	Property, equipment, and mine development costs consisted of the following:
		December 31,
		2014		2013
	Plant and mining equipment	$	3,351,521	$	3,731,282
	Mine development	281,594		299,334
	Office equipment, software and other	49,784		61,000
	Construction in progress	64,212		62,457
	Total property, equipment and mine development costs	3,747,111		4,154,073
	Less accumulated depreciation and amortization	2,321,444		2,355,425
	Total property, equipment and mine development costs, net	$	1,425,667	$	1,798,648

Goodwill_and_Other_Acquired_In1

Goodwill and Other Acquired Intangibles, Net (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill
		Balance as of			Impairments			Balance as of
		December 31, 2013						December 31, 2014
	Goodwill:
	Eastern operations	$	3,024,308		$	—		$	3,024,308
	Accumulated impairment losses:
	Eastern operations	$	(2,715,657	)	$	(308,651	)	$	(3,024,308	)
	Goodwill, net:
	Eastern operations	$	308,651		$	(308,651	)	$	—
		Balance as of			Impairments/Disposals			Balance as of
		December 31, 2012						December 31, 2013
	Goodwill:
	Eastern operations	$	3,024,308		$	—		$	3,024,308
	Western operations	53,308			—			53,308
	All other	5,912			(5,912		)	—
	Total goodwill	$	3,083,528		$	(5,912	)	$	3,077,616
	Accumulated impairment losses:
	Eastern operations	$	(2,462,555	)	$	(253,102	)	$	(2,715,657	)
	Western operations	(53,308		)	—			(53,308		)
	All other	—			—			—
	Total accumulated impairment losses	$	(2,515,863	)	$	(253,102	)	$	(2,768,965	)
	Goodwill, net:
	Eastern operations	$	561,753		$	(253,102	)	$	308,651
	Western operations	—			—			—
	All other	5,912			(5,912		)	—
	Total goodwill, net	$	567,665		$	(259,014	)	$	308,651
Other acquired intangibles	Other Acquired Intangibles:
		December 31, 2014
		Acquisition value			Accumulated			Balance, net
					amortization
	Assets:
	Above-market coal supply and transportation agreements	$	374,509		$	(305,003	)	$	69,506
	Mining permits	101,073			(73,410		)	27,663
	Total (1)	$	475,582		$	(378,413	)	$	97,169
	Liabilities:
	Below-market coal supply agreements (2)	$	580,327		$	(548,169	)	$	32,158
		December 31, 2013
		Acquisition value			Accumulated			Balance, net
					amortization
	Assets:
	Above-market coal supply and transportation agreements	$	479,361		$	(365,448	)	$	113,913
	Mining permits	101,841			(57,289		)	44,552
	Total (1)	$	581,202		$	(422,737	)	$	158,465
	Liabilities:
	Below-market coal supply agreements (2)	$	605,281		$	(551,035	)	$	54,246
	(1)	Reported as other acquired intangibles in the Consolidated Balance Sheets.
	(2)	Reported in other long-term liabilities in the Consolidated Balance Sheets.

Other_Noncurrent_Assets_Tables

Other Non-current Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Other Assets, Noncurrent [Abstract]
Details of other non-current assets	Other non-current assets consisted of the following:
		December 31,
		2014		2013
	Marketable securities - long term (1)	$	136,927	$	9,330
	Unamortized deferred financing costs, net	96,682		94,672
	Advance mining royalties, net	51,530		60,310
	Virginia tax credit, net	21,469		22,124
	Equity method investments (2)	71,224		151,382
	Insurance receivables	20,337		24,281
	Other	22,522		25,465
	Total other non-current assets	$	420,691	$	387,564
	(1)	See Note 7.
	(2)	The equity method investment balances include the company’s Marcellus gas joint venture with EDF Trading Resources, LLC, a fifty percent owner with Alpha.

Accrued_Expenses_and_Other_Cur1

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2014
Accounts Payable and Accrued Liabilities, Current [Abstract]
Schedule of accrued expenses and other current liabilities	Accrued expenses and other current liabilities consisted of the following:
		December 31,
		2014		2013
	Wages and employee benefits	$	111,627	$	117,561
	Current portion of asset retirement obligations	102,493		70,851
	Taxes other than income taxes	108,504		123,361
	Interest payable	45,612		22,321
	Current portion of postretirement medical benefit obligations	46,678		46,678
	Deferred revenue	27,488		41,250
	Litigation (1)	51,280		447,214
	Other	121,518		109,459
	Total accrued expenses and other current liabilities	$	615,200	$	978,695
	(1) The Company has recorded related receivables of $41,283 and $195,228 from insurance coverage and indemnifications in prepaid expenses and other current assets at December 31, 2014 and 2013, respectively.

LongTerm_Debt_Tables

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2014
Long-term Debt, Unclassified [Abstract]
Schedule of Long-term Debt	Long-term debt consisted of the following:
		December 31,
		2014			2013
	2.375% convertible senior notes due 2015	$	44,458		$	65,889
	3.25% convertible senior notes due 2015	109,201			128,182
	3.75% convertible senior notes due 2017	345,000			345,000
	9.75% senior notes due 2018	500,000			500,000
	6.00% senior notes due 2019	800,000			800,000
	4.875% convertible senior notes due 2020	345,000			345,000
	7.50% senior secured second lien notes due 2020	500,000			—
	Term loan due 2020	614,062			620,313
	6.25% senior notes due 2021	700,000			700,000
	Other	61,344			73,305
	Debt discount, net	(121,295		)	(150,086		)
	Total long-term debt	$	3,897,770		$	3,427,603
	Less current portion	(178,251		)	(29,169		)
	Long-term debt, net of current portion	$	3,719,519		$	3,398,434
Schedule of maturities of long-term debt	Future maturities of long-term debt as of December 31, 2014 are as follows:
	2015	$	180,177
	2016	15,887
	2017	363,065
	2018	506,676
	2019	806,574
	Thereafter	2,146,686
	Total long-term debt	$	4,019,065

Asset_Retirement_Obligations_T

Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2014
Asset Retirement Obligation [Abstract]
Schedule of changes in the asset retirement obligations	Changes in the asset retirement obligations were as follows:
	Total asset retirement obligations at December 31, 2012	$	856,701
	Accretion for the period	60,274
	Sites added during the period	1,667
	Revisions in estimated cash flows (1)	(74,354		)
	Expenditures for the period	(44,862		)
	Total asset retirement obligations at December 31, 2013	799,426
	Accretion for the period	47,698
	Sites added during the period	2,685
	Revisions in estimated cash flows (1) (2)	(133,680		)
	Asset sales	(20,108		)
	Expenditures for the period	(55,520		)
	Total asset retirement obligations at December 31, 2014	$	640,501
	Less current portion	(102,493		)
	Long-term portion	$	538,008
	(1)	Amount includes $107,263 and $66,521, primarily related to changes in the discount rate, which were recorded as a reduction to cost of coal sales in the Consolidated Statements of Operations for the years ended December 31, 2014 and 2013, respectively.
	(2)	During the fourth quarter of 2014, the Company discovered a programming logic error in the system used to calculate its asset retirement obligations. The faulty logic caused liability amounts for certain permits in certain circumstances to be miscalculated and the asset retirement obligations related to these permits were overstated in 2013 and 2012. The programming logic was corrected and the Company determined that the errors were immaterial to the Company's financial statements in 2013 and 2012, and therefore, were corrected in the fourth quarter of 2014. The Company corrected these errors by decreasing its asset retirement obligations by $51,361, cost of coal sales by $29,987 and depreciation, depletion and amortization by $13,583 for the year ended December 31, 2014. This resulted in a decrease of $43,570 to loss from operations and net loss for the year ended December 31, 2014.

Other_Noncurrent_Liabilities_T

Other Non-current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2014
Other Liabilities, Noncurrent [Abstract]
Schedule of other non-current liabilities	Other non-current liabilities consisted of the following:
		December 31,
		2014		2013
	Self insured workers’ compensation obligations	$	137,824	$	142,537
	Black lung obligations	144,894		136,457
	Below-market and other contract-related obligations, net (1)	109,908		95,885
	Deferred coal revenue	23,021		33,138
	Other	56,173		57,875
	Total other non-current liabilities	$	471,820	$	465,892

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments and Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Schedule of fair values of financial instruments	:
		December 31, 2014
		Carrying			Total Fair		Quoted Prices			Significant		Significant
		Amount			Value		in Active			Other		Unobservable
							Markets			Observable		Inputs
							(Level 1)			Inputs		(Level 3)
										(Level 2)
	6.25% senior notes due 2021	$	700,000		$	208,950	$	208,950		$	—	$	—
	7.50% senior secured second lien notes due 2020	500,000			320,000		320,000			—		—
	6.00% senior notes due 2019	800,000			240,000		240,000			—		—
	9.75% senior notes due 2018 (1)	497,779			233,430		233,430			—		—
	Term loan due 2020 (2)	611,655			499,424		—			499,424		—
	4.875% convertible senior notes due 2020 (3)	272,886			125,494		125,494			—		—
	3.75% convertible senior notes due 2017 (4)	302,378			172,500		172,500			—		—
	3.25% convertible senior notes due 2015 (5)	108,225			104,014		104,014			—		—
	2.375% convertible senior notes due 2015 (6)	43,503			43,368		43,368			—		—
	Total long-term debt	$	3,836,426		$	1,947,180	$	1,447,756		$	499,424	$	—
		December 31, 2013
		Carrying			Total Fair		Quoted Prices			Significant		Significant
		Amount			Value		in Active			Other		Unobservable
							Markets			Observable		Inputs
							(Level 1)			Inputs		(Level 3)
										(Level 2)
	6.25% senior notes due 2021	$	700,000		$	602,000	$	602,000		$	—	$	—
	6.00% senior notes due 2019	800,000			694,872		694,872			—		—
	9.75% senior notes due 2018 (1)	496,547			560,250		560,250			—		—
	Term loan due 2020 (2)	617,460			617,291		—			617,291		—
	4.875% convertible senior notes due 2020 (3)	264,283			372,606		372,606			—		—
	3.75% convertible senior notes due 2017 (4)	290,219			360,956		360,956			—		—
	3.25% convertible senior notes due 2015 (5)	125,142			126,904		126,904			—		—
	2.375% convertible senior notes due 2015 (6)	60,647			65,882		65,882			—		—
	Total long-term debt	$	3,354,298		$	3,400,761	$	2,783,470		$	617,291	$	—
	(1)	Net of debt discount of $2,221 and $3,453 as of December 31, 2014 and 2013, respectively.
	(2)	Net of debt discount of $2,407 and $2,853 as of December 31, 2014 and 2013, respectively.
	(3)	Net of debt discount of $72,114 and $80,717 as of December 31, 2014 and 2013, respectively.
	(4)	Net of debt discount of $42,622 and $54,781 as of December 31, 2014 and 2013, respectively.
	(5)	Net of debt discount of $976 and $3,040 as of December 31, 2014 and 2013, respectively.
	(6)	Net of debt discount of $955 and $5,242 as of December 31, 2014 and 2013, respectively.
Schedule of fair value of assets and liabilities measured on recurring and nonrecurring basis
		December 31, 2014
		Total Fair			Quoted Prices		Significant Other			Significant
		Value			in Active		Observable			Unobservable
					Markets		Inputs			Inputs
					(Level 1)		(Level 2)			(Level 3)
	Financial assets (liabilities):
	U.S. treasury and agency securities	$	80,093		$	80,093	$	—		$	—
	Mutual funds held in rabbi trust	$	10,107		$	10,107	$	—		$	—
	Corporate equity securities	$	126,820		$	126,820	$	—		$	—
	Corporate debt securities	$	325,076		$	—	$	325,076		$	—
	Forward coal sales	$	760		$	—	$	760		$	—
	Commodity swaps	$	(23,614	)	$	—	$	(23,614	)	$	—
		December 31, 2013
		Total Fair			Quoted Prices		Significant Other			Significant
		Value			in Active		Observable			Unobservable
					Markets		Inputs			Inputs
					(Level 1)		(Level 2)			(Level 3)
	Financial assets (liabilities):
	U.S. treasury and agency securities	$	81,497		$	81,497	$	—		$	—
	Mutual funds held in rabbi trust	$	9,330		$	9,330	$	—		$	—
	Corporate debt securities	$	255,572		$	—	$	255,572		$	—
	Forward coal sales	$	(398	)	$	—	$	(398	)	$	—
	Commodity swaps	$	10,403		$	—	$	10,403		$	—

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedges, Assets [Abstract]
Schedule of derivative assets at fair value	The following tables present the fair values and location of the Company’s derivative instruments within the Consolidated Balance Sheets:
				Asset Derivatives
	Derivatives not designated as	Statement of Financial Position Location		December 31,			December 31,
	cash flow hedging instruments			2014			2013
	Commodity swaps	Prepaid expenses and other current assets		$	429		$	8,898
	Commodity swaps	Other non-current assets		—			1,772
	Forward coal sales	Prepaid expenses and other current assets		760			—
				$	1,189		$	10,670
Schedule of derivative liabilities at fair value
				Liability Derivatives
	Derivatives not designated as	Statement of Financial Position Location		December 31,			December 31,
	cash flow hedging instruments			2014			2013
	Commodity swaps	Other non-current liabilities		$	3,022		$	31
	Commodity swaps	Accrued expenses and other current liabilities		21,021			236
	Forward coal sales	Accrued expenses and other current liabilities		—			398
				$	24,043		$	665
Gains and losses on derivatives designated as cash flow hedging instruments	The following tables present the gains and losses from derivative instruments for the years ended December 31, 2014, 2013, and 2012 and their location within the Consolidated Financial Statements:
			Gain (loss) reclassified from accumulated other									Gain (loss) recorded in accumulated other comprehensive income (loss)
			comprehensive income (loss) to earnings
	Derivatives designated as		2014			2013			2012			2014		2013			2012
	cash flow hedging instruments
	Commodity swaps (1) (3)		$	2,341		$	1,911		$	10,390		$	—	$	(908	)	$	13,831
	Commodity options (2) (3)		—			(68		)	—			—		(63		)	(19		)
			$	2,341		$	1,843		$	10,390		$	—	$	(971	)	$	13,812
	(1)	For the twelve months ended December 31, 2014, amounts included in cost of coal sales and coal revenues in the Consolidated Statements of Operations. For the twelve months ended December 31, 2013 and 2012, amounts included in cost of coal sales, other revenues and coal revenues in the Consolidated Statements of Operations.
	(2)	Amounts are recorded in other revenues in the Consolidated Statements of Operations.
	(3)	Net of tax.
Gains and losses on derivatives not designated as cash flow hedging instruments
			Gain (loss) recorded in earnings
	Derivatives not designated as		2014			2013			2012
	cash flow hedging instruments
	Forward coal sales (1)		$	1,158		$	(15,756	)	$	(11,887	)
	Forward coal purchases (1)		—			4			15,452
	Commodity swaps (2)		(26,910		)	9,539			348
	Commodity options-coal (1)		—			—			17
	Interest rate swaps (3)		—			—			(400		)
	Total		$	(25,752	)	$	(6,213	)	$	3,530
	(1)	Amounts are recorded as a component of other revenues in the Consolidated Statements of Operations.
	(2)	Amounts are recorded as a component of coal revenues, cost of coal sales and other expenses in the Consolidated Statements of Operations.
	(3)	Amount is recorded as a component of interest expense in the Consolidated Statements of Operations.

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of significant components of income tax expense (benefit) from continuing operations	Significant components of income tax expense (benefit) were as follows:
		Years Ended December 31,
		2014			2013			2012
	Current tax (benefit) expense:
	Federal	$	(15,430	)	$	(3,949	)	$	(1,686	)
	State	616			(240		)	6,265
		$	(14,814	)	$	(4,189	)	$	4,579
	Deferred tax benefit:
	Federal	$	(24,886	)	$	(203,560	)	$	(482,015	)
	State	(15,591		)	(8,801		)	(72,560		)
		$	(40,477	)	$	(212,361	)	$	(554,575	)
	Total income tax benefit:
	Federal	$	(40,316	)	$	(207,509	)	$	(483,701	)
	State	(14,975		)	(9,041		)	(66,295		)
		$	(55,291	)	$	(216,550	)	$	(549,996	)
Schedule of reconciliation of statutory federal income tax expense to income from continuing operations before income taxes and the actual income tax expense (benefit)	A reconciliation of the statutory federal income tax benefit at 35% to the actual income tax benefit is as follows:
		Years Ended December 31,
		2014			2013			2012
	Federal statutory income tax benefit	$	(325,588	)	$	(465,517	)	$	(1,045,500	)
	Increases (reductions) in taxes due to:
	Percentage depletion allowance	(28,630		)	(34,702		)	(76,252		)
	State taxes, net of federal tax impact	(2,891		)	(49,523		)	(25,748		)
	State tax rate and NOL change, net of federal tax benefit	—			(2,524		)	(8,180		)
	Change in valuation allowances	196,646			207,681			43,885
	Non-deductible stock-based compensation	6,627			5,509			—
	Non-deductible fines and penalties	2,349			14,513			3,996
	State apportionment change, net of federal tax impact	(5,811		)	15,425			(18,654		)
	Non-deductible goodwill impairment	108,028			88,586			572,503
	Reversal of reserves for uncertain tax positions	(8,090		)	—			—
	Other, net	2,069			4,002			3,954
	Income tax benefit	$	(55,291	)	$	(216,550	)	$	(549,996	)
Schedule of net deferred tax assets and liabilities included in the Consolidated Balance Sheets	The net deferred tax assets and liabilities included in the Consolidated Balance Sheets include the following amounts:
		December 31,
		2014			2013
	Deferred tax assets:
	Asset retirement obligations	$	236,389		$	297,405
	Reserves and accruals not currently deductible	80,492			145,870
	Pension and postretirement medical obligations	460,252			374,662
	Alternative minimum tax credit carryforwards	208,759			210,742
	Goodwill	28,060			31,700
	Workers’ compensation obligations	107,557			104,424
	Acquired intangibles, net	15,870			6,469
	Deferred revenue	19,095			28,080
	Other	47,541			36,101
	Net operating loss carryforwards	1,002,863			797,284
	Gross deferred tax assets	2,206,878			2,032,737
	Less valuation allowance	(563,142		)	(294,073		)
	Total net deferred tax assets	1,643,736			1,738,664
	Deferred tax liabilities:
	Property, equipment and mineral reserves	(2,218,426		)	(2,367,180		)
	Debt discount	(43,059		)	(53,490		)
	Prepaid expenses	(43,822		)	(57,411		)
	Equity and cost method investments and marketable securities	(48,715		)	(31,177		)
	Other	(8,729		)	(12,201		)
	Total deferred tax liabilities	(2,362,751		)	(2,521,459		)
	Net deferred tax liability	$	(719,015	)	$	(782,795	)
Schedule of breakdown of net deferred tax liability	The breakdown of the net deferred tax liability as recorded in the accompanying Consolidated Balance Sheets is as follows:
		December 31,
		2014			2013
	Current asset	$	54,451		$	118,757
	Noncurrent liability	(773,466		)	(901,552		)
	Total net deferred tax liability	$	(719,015	)	$	(782,795	)
Schedule of changes in the valuation allowance	Changes in the valuation allowance during the years ended December 31, 2014, 2013 and 2012 were as follows:
		December 31,
		2014			2013			2012
	Valuation allowance beginning of period	$	294,073		$	86,392		$	41,940
	Increase in valuation allowance not affecting income tax expense	72,423			—			567
	Increase in valuation allowance recorded as an increase to income tax expense	196,646			207,681			43,885
	Valuation allowance end of period	$	563,142		$	294,073		$	86,392
Schedule of reconciliation of Company's liability for uncertain tax positions	The following reconciliation illustrates the Company’s liability for uncertain tax positions:
		December 31,
		2014			2013			2012
	Unrecognized tax benefits — beginning of period	$	28,741		$	28,741		$	28,741
	Reduction as a result of settlement with taxing authorities	(26,020		)	—			—
	Unrecognized tax benefits - end of period	$	2,721		$	28,741		$	28,741

Employee_Benefit_Plans_Tables

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2014
Company Administered Postretirement Health Care and Life Insurance Benefits
Defined Benefit Plan Disclosure [Line Items]
Schedule of change in accumulated benefit obligations	The components of the change in accumulated benefit obligations of the plans for postretirement medical benefits were as follows:
		December 31,
		2014				2013
	Change in benefit obligations:
	Accumulated benefit obligation-beginning period:	$	942,693			$	1,006,193
	Service cost	11,145				13,785
	Interest cost	42,018				40,170
	Actuarial loss (gain)	129,270				(84,769		)
	Benefits paid	(34,977		)		(32,686		)
	Change in plan provisions	(26,196		)		—
	Accumulated benefit obligation-end of period	$	1,063,953			$	942,693
	Change in fair value of plan assets:
	Employer contributions	$	34,977			$	32,686
	Benefits paid	(34,977		)		(32,686		)
	Fair value of plan assets at December 31	—				—
	Funded status	$	(1,063,953	)		$	(942,693	)
	Amounts recognized in the consolidated balance sheets:
	Current liabilities	$	(46,678	)		$	(46,678	)
	Long-term liabilities	(1,017,275		)		(896,015		)
		$	(1,063,953	)		$	(942,693	)
	Amounts recognized in accumulated other comprehensive (income) loss:
	Prior service credit	$	(48,048	)		$	(24,521	)
	Net actuarial loss	193,559				64,288
		$	145,511			$	39,767
Schedule of components of the net periodic benefit cost	The following table details the components of the net periodic benefit cost for postretirement medical benefits:
		Years Ended December 31,
		2014				2013			2012
	Service cost	$	11,145			$	13,785		$	16,408
	Interest cost	42,018				40,170			42,122
	Amortization of net actuarial loss	—				2,872			4,656
	Amortization of prior service credit	(4,477		)		(3,819		)	(641		)
	Net periodic benefit cost	$	48,686			$	53,008		$	62,545
Schedule of changes in plan assets and benefit obligations recognized in other comprehensive (income) loss	Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss are as follows:
		Years Ended December 31,
		2014				2013			2012
	Current year actuarial loss (gain)	$	129,270			$	(84,769	)	$	(47,753	)
	Prior service credit for period	(28,003		)		—			(44,835		)
	Amortization of net actuarial (loss)	—				(2,872		)	(4,656		)
	Amortization of prior service credit	4,477				3,819			641
	Total recognized in other comprehensive loss (income)	$	105,744			$	(83,822	)	$	(96,603	)
	Total recognized in net periodic benefit cost and other comprehensive loss (income)	$	154,429			$	(30,815	)	$	(34,058	)
Schedule of estimated amount that will be amortized from accumulated other comprehensive (loss) income into net period benefit cost	The estimated amount that will be amortized from accumulated other comprehensive (income) loss into net period benefit cost in 2015 is as follows:
	Prior service credit	$	(4,477	)
Schedule of Assumptions Used [Table Text Block]	The weighted-average assumptions used to determine the postretirement plans’ benefit obligation as of December 31, 2014 and 2013 were as follows:
		December 31,
		2014			2013
	Discount rate	3.93	%		4.68	%
	The weighted average discount rates used in determining net periodic postretirement medical benefit cost for the years ended December 31, 2014, 2013, and 2012 were as follows:
		Years Ended December 31,
		2014		2013		2012
	Discount rate	4.56%		4.18%		4.10%
Schedule of health care cost trend rate	The following presents information about the postretirement plans’ weighted-average annual rate of increase in the per capita cost of covered benefits (i.e., health care cost trend rate):
	Health care cost trend rate assumed for the next year	7.5	%
	Rate to which the cost trend is assumed to decline (ultimate trend rate)	5	%
	Year that the rate reaches the ultimate trend rate	2020
Schedule of effects of one-percentage-point change in assumed health care trend rates	A one-percentage-point change in assumed health care trend rates would have the following effects as of and for the year ended December 31, 2014:
		One Percentage				One Percentage
		Point Increase				Point Decrease
	Effect on total service and interest cost components	$	8,250			$	(6,646	)
	Effect on accumulated postretirement benefit obligation	$	157,163			$	(126,240	)
Schedule of expected future benefit payments for the next ten years	The following represents the Company’s expected future postretirement medical and life insurance benefit payments for the next ten years, which reflect expected future service, as appropriate:
		Postretirement
		Medical and
		Life Insurance
		Benefits
	2015	$	46,076
	2016	51,233
	2017	53,748
	2018	55,574
	2019	56,381
	2019-2023	274,273
		$	537,285
Company Administered Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Schedule of benefit obligations, fair value of plan assets and funded status	The following tables set forth the plans’ accumulated benefit obligations, fair value of plan assets and funded status:
		December 31,
		2014				2013
	Change in benefit obligation:
	Accumulated benefit obligation at beginning of period	$	629,379			$	792,383
	Interest cost	31,210				29,497
	Actuarial loss (gain)	145,609				(135,832		)
	Benefits paid	(24,311		)		(23,607		)
	Settlements	(13,142		)		(33,062		)
	Accumulated benefit obligation at end of period	$	768,745			$	629,379
	Change in fair value of plan assets:
	Fair value of plan assets at beginning of period	$	535,270			$	561,151
	Actual return on plan assets	44,420				27,786
	Employer contributions	6,797				3,002
	Benefits paid	(24,311		)		(23,607		)
	Settlements	(13,142		)		(33,062		)
	Fair value of plan assets at end of period	549,034				535,270
	Funded status	(219,711		)		(94,109		)
	Accrued benefit cost at end of year	$	(219,711	)		$	(94,109	)
Schedule of gross amounts recognized in accumulated other comprehensive (income) loss	Gross amounts recognized in accumulated other comprehensive (income) loss were as follows:
		Years Ended December 31,
		2014				2013
	Net actuarial loss	$	146,866			$	12,631
Schedule of components of the net periodic benefit cost	The following table details the components of net periodic benefit credit:
		Years Ended December 31,
		2014				2013			2012
	Service cost	$	—			$	—		$	—
	Interest cost	31,210				29,497			31,990
	Expected return on plan assets	(35,207		)		(36,199		)	(38,798		)
	Amortization of net actuarial loss	10				822			1,837
	Settlement loss (gain)	2,151				(212		)	1,207
	Total	$	(1,836	)		$	(6,092	)	$	(3,764	)
Schedule of changes in plan assets and benefit obligations recognized in other comprehensive (income) loss	Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss are as follows:
		Years Ended December 31,
		2014				2013			2012
	Current year actuarial loss (gain)	$	136,396			$	(127,419	)	$	67,042
	Amortization of net actuarial loss	(10		)		(822		)	(1,837		)
	Settlement (loss) gain	(2,151		)		212			(1,207		)
	Total recognized in other comprehensive loss (income)	$	134,235			$	(128,029	)	$	63,998
	Total recognized in net periodic benefit cost and other comprehensive loss (income)	$	132,399			$	(134,121	)	$	60,234
Schedule of estimated amount that will be amortized from accumulated other comprehensive (loss) income into net period benefit cost	be amortized from accumulated other comprehensive (income) loss into net period benefit cost in 2015.
Schedule of Assumptions Used [Table Text Block]	The weighted-average actuarial assumptions used to determine net periodic benefit cost for the years ended December 31, 2014 and 2013 were as follows:
		December 31,
		2014		2013		2012
	Discount rate	4.93%		4.21%		4.22%
	Rate of increase in future compensation (a)	N/A		N/A		N/A
	Expected long-term return on plan assets	6.75%		6.75%		7.25%
	Measurement date	December 31, 2014		December 31, 2013		December 31, 2012
	The weighted-average actuarial assumptions used in determining the benefit obligations as of December 31, 2014 and 2013 were as follows:
		December 31,
		2014		2013
	Discount rate	4.00%		4.87%
Schedule of accumulated benefit obligations in excess of plan assets	The following table presents information applicable to plans with accumulated benefit obligations in excess of plan assets:
		December 31,
		2014				2013
	Projected benefit obligation	$	768,745			$	629,379
	Accumulated benefit obligation	$	768,745			$	629,379
	Fair value of plan assets	$	549,034			$	535,270
Schedule of target allocation and actual asset allocation	The target allocation for 2015 and the actual asset allocation as reported at December 31, 2014 is as follows:
		Target			Percentage of
		Allocation			Plan Assets
		Percentages			2014
		2015
	Equity funds	38	%		44	%
	Fixed income funds	60	%		54	%
	Private equity funds/guaranteed insurance contract	2	%		2	%
	Total	100	%		100	%
Schedule of expected future benefit payments for the next ten years	The following represents expected future pension benefit and SERP payments for the next ten years:
	2015	$	29,530
	2016	30,427
	2017	31,830
	2018	33,004
	2019	34,089
	2019-2023	182,079
		$	340,959
Schedule of fair value of plan assets by category	The fair values of the Company’s Pension Plans’ assets as of December 31, 2014, by asset category are as follows:
						Quoted Market			Significant				Significant
						Prices in Active			Observable				Unobservable
						Market for			Inputs				Inputs
						Identical
						Assets
	Asset Category	Total				(Level 1)			(Level 2)				(Level 3)
	Equity securities:
	Multi-asset fund (a)	$	211,425			$	—		$	211,425			$	—
	Fixed income securities:
	Bond fund (b)	320,574				—			320,574				—
	Other types of investments:
	Private equity funds (c)	5,040				—			—				5,040
	Guaranteed insurance contract	10,062				—			—				10,062
	Total	$	547,101			$	—		$	531,999			$	15,102
	Receivable (d)	1,933
	Total	$	549,034
	(a)	This fund contains equities (domestic and international), real estate, and bonds.
	(b)	This fund contains bonds representing a diversity of sectors and maturities. This fund also includes mortgage-backed securities and U.S. Treasuries.
	(c)	This category includes several private equity funds that invest primarily in U.S. and European markets.
	(d)	Receivable for investments sold at December 31, 2014, which approximates fair value.
	The fair values of the Company’s Pension Plans’ assets as of December 31, 2013, by asset category are as follows:
						Quoted Market			Significant				Significant
						Prices in Active			Observable				Unobservable
						Market for			Inputs				Inputs
						Identical
						Assets
	Asset Category	Total				(Level 1)			(Level 2)				(Level 3)
	Equity securities:
	Multi-asset fund (a)	$	238,699			$	—		$	238,699			$	—
	Fixed income securities:
	Bond fund (b)	280,434				—			280,434				—
	Other types of investments:
	Private equity funds (c)	5,480				—			—				5,480
	Guaranteed insurance contract	9,732				—			—				9,732
	Total	$	534,345			$	—		$	519,133			$	15,212
	Receivable (d)	925
	Total	$	535,270
	(a)	This fund contains equities (domestic and international), real estate, and bonds.
	(b)	This fund contains bonds representing a diversity of sectors and maturities. This fund also includes mortgage-backed securities and U.S. Treasuries.
	(c)	This category includes several private equity funds that invest primarily in U.S. and European markets.
	(d)	Receivable for investments sold at December 31, 2013, which approximates fair valu
Schedule of changes in level 3 plan assets
	Changes in level 3 plan assets for the year ended December 31, 2014 were as follows:
			Fair Value Measurements Using Significant
			Unobservable Inputs (Level 3)
			Private				Guaranteed			Total
			Equity				Insurance
			Funds				Contract
	Beginning balance, December 31, 2013		$	5,480			$	9,732		$	15,212
	Actual return on plan assets:
	Relating to assets still held at the reporting date		601				—			601
	Relating to assets sold during the period		177				—			177
	Purchases, sales, and settlements		(1,218		)		330			(888		)
	Ending balance, December 31, 2014		$	5,040			$	10,062		$	15,102
	Changes in level 3 plan assets for the year ended December 31, 2013 were as follows:
Workers' Compensation and Pneumoconiosis (Black lung)
Defined Benefit Plan Disclosure [Line Items]
Schedule of benefit obligations, fair value of plan assets and funded status
	The following tables set forth the accumulated black lung benefit obligations, fair value of plan assets and funded status for the years ended December 31, 2014 and 2013:
		December 31,
		2014				2013
	Change in benefit obligation:
	Accumulated benefit obligation at beginning of period	$	156,608			$	145,271
	Service cost	2,199				2,708
	Interest cost	7,125				6,577
	Actuarial loss	7,417				11,294
	Benefits paid	(9,010		)		(9,242		)
	Plan amendments	6,336				—
	Accumulated benefit obligation at end of period	$	170,675			$	156,608
	Change in fair value of plan assets:
	Fair value of plan assets at beginning of period	$	12,009			$	3,431
	Actual return on plan assets	13				(19		)
	Benefits paid	(9,010		)		(9,242		)
	Employer contributions	9,053				17,839
	Fair value of plan assets at end of period (1)	12,065				12,009
	Funded status	(158,610		)		(144,599		)
	Accrued benefit cost at end of year	$	(158,610	)		$	(144,599	)
	Amounts recognized in the consolidated balance sheets:
	Current liabilities	$	13,716			$	8,142
	Long-term liabilities	144,894				136,457
		$	158,610			$	144,599
	(1)	Assets of the plan are held in a Section 501(c)(21) tax-exempt trust fund and consist primarily of government debt securities. All assets are classified as Level 1 and valued based on quoted market price
Schedule of gross amounts recognized in accumulated other comprehensive (income) loss
	Gross amounts related to the black lung obligations recognized in accumulated other comprehensive (income) loss consisted of the following as of December 31, 2014 and 2013:
Schedule of components of the net periodic benefit cost
	The following table details the components of the net periodic benefit cost for black lung obligations:
Schedule of changes in plan assets and benefit obligations recognized in other comprehensive (income) loss
	Other changes in the black lung plan assets and benefit obligations recognized in other comprehensive (income) loss are as follows:
Schedule of Assumptions Used [Table Text Block]
	The weighted-average assumptions related to black lung obligations used to determine net periodic benefit cost were as follows:
	The weighted-average assumptions related to black lung obligations used to determine the benefit obligation as of December 31, 2014 and 2013 were as follows:
Schedule of expected future benefit payments for the next ten years
	Estimated future cash payments related to black lung obligations for the next ten years ending after December 31, 2014 are as follows:

StockBased_Compensation_Awards1

Stock-Based Compensation Awards (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of time-based share unit activity	Time-based share unit activity for the year ended December 31, 2014 is summarized in the following table:
		Number of		Weighted-
		Shares		Average
				Grant Date
				Fair Value
	Non-vested shares outstanding at December 31, 2013	3,099,289		$	11.66
	Granted	1,632,824		$	4.25
	Vested	(906,424	)	$	16.26
	Forfeited or Expired	(57,256	)	$	10.34
	Non-vested shares outstanding at December 31, 2014	3,768,433		$	7.32
Summary of performance-based share unit activity	Performance-based share unit activity for the year ended December 31, 2014 is summarized in the following table:
		Number of		Weighted-
		Shares (1)		Average
				Grant Date
				Fair Value
	Non-vested shares outstanding at December 31, 2013	5,566,158		$	15.25
	Granted	2,756,972		$	4.33
	Earned	(11,027	)	$	2.6
	Forfeited or expired	(493,472	)	$	58.6
	Non-vested shares outstanding at December 31, 2014	7,818,631		$	8.78
Summary of stock option activity	Stock option activity for the year ended December 31, 2014 is summarized in the following table:
		Number of		Weighted-			Weighted-
		Shares		Average			Average
				Exercise			Remaining
				Price			Contractual
							Term (Years)
	Outstanding at December 31, 2013	937,977		$	21.77
	Exercised	—		$	—
	Forfeited or Expired	(351,255	)	$	15.58
	Outstanding at December 31, 2014	586,722		$	25.48		3.41
	Exercisable at December 31, 2014	586,722		$	25.48		3.41
Summary of options outstanding and exercisable	A summary of the Company’s options outstanding and exercisable at December 31, 2014 follows:
			Options Outstanding and Exercisable
	Exercise		Shares		Weighted-	Weighted-
	Price				Average	Average
					Remaining	Exercise
					Life (yrs)	Price
	$ 11.15-$20.44		278,429		2.39	$	17.42
	$ 23.93-$32.91		199,518		3.52	$	28.29
	$ 40.98-$48.26		108,775		5.88	$	41.04
			586,722		3.41	$	25.48

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Schedule of aggregate future minimum non-cancelable lease payments under operating leases and minimum royalties under coal leases	As of December 31, 2014, aggregate future minimum non-cancelable lease payments under operating leases and minimum royalties under coal leases were as follows:
		Operating			Coal
		Leases			Royalties
	Year Ending December 31:
	2015	$	5,282		$	38,494
	2016	793			35,192
	2017	150			33,669
	2018	—			25,546
	2019	—			13,450
	Thereafter	—			65,215
	Total	$	6,225		$	211,566
Schedule of Future Minimum Lease Payments for Capital Leases [Table Text Block]	The following is a schedule by years of future minimum lease payments under capital leases together with the present value of the net minimum lease payments as of December 31, 2014:
		Capital Leases
	Year Ending December 31:
	2015	$	19,311
	2016	12,067
	2017	9,966
	2018	3,057
	2019	2,962
	Thereafter	48,479
	Total minimum lease payments	$	95,842
	Less: Amount representing interest (rates range from 0.15% to 13.86%)	(44,480		)
	Present value of net minimum lease payments	$	51,362

Segment_Information_Tables

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Schedule of segment operating results and capital expenditure from continuing operations	Segment operating results and capital expenditures for the year ended December 31, 2014 were as follows:
		Eastern			Western			All			Consolidated
		Coal			Coal			Other
		Operations			Operations
	Total revenues	$	3,803,396		$	443,953		$	39,729		$	4,287,078
	Depreciation, depletion and amortization(1)	$	670,520		$	59,591		$	20,665		$	750,776
	Amortization of acquired intangibles, net	$	41,149		$	(2,119	)	$	176		$	39,206
	EBITDA(1)(2)	$	188,337		$	16,053		$	(58,459	)	$	145,931
	Capital expenditures	$	170,063		$	12,562		$	2,413		$	185,038
	Acquisition of mineral rights under federal lease	$	—		$	42,130		$	—		$	42,130
	Segment operating results and capital expenditures for the year ended December 31, 2013 were as follows:
		Eastern			Western			All			Consolidated
		Coal			Coal			Other
		Operations			Operations
	Total revenues	$	4,412,334		$	487,324		$	53,850		$	4,953,508
	Depreciation, depletion and amortization	$	780,120		$	54,265		$	30,636		$	865,021
	Amortization of acquired intangibles, net	$	7,916		$	(2,878	)	$	18		$	5,056
	EBITDA(1)	$	(44,223	)	$	90,879		$	(263,556	)	$	(216,900	)
	Capital expenditures	$	207,503		$	5,369		$	2,789		$	215,661
	Acquisition of mineral rights under federal lease	$	—		$	42,130		$	—		$	42,130
	Segment operating results and capital expenditures for the year ended December 31, 2012 were as follows:
		Eastern			Western			All			Consolidated
		Coal			Coal			Other
		Operations			Operations
	Total revenues	$	6,290,289		$	611,329		$	73,266		$	6,974,884
	Depreciation, depletion and amortization	$	949,064		$	62,729		$	25,782		$	1,037,575
	Amortization of acquired intangibles, net	$	(87,875	)	$	13,644		$	3,893		$	(70,338	)
	EBITDA(1)	$	(1,807,515	)	$	65,153		$	(82,771	)	$	(1,825,133	)
	Capital expenditures	$	368,838		$	18,082		$	15,457		$	402,377
	Acquisition of mineral rights under federal lease	$	—		$	95,765		$	—		$	95,765
Schedule of reconciliation of EBITDA from continuing operations to income from continuing operations for the year	The following table presents a reconciliation of EBITDA to net loss for the years ended:
		December 31,
		2014			2013			2012
	EBITDA	$	145,931		$	(216,900	)	$	(1,825,133	)
	Interest expense	(288,466		)	(246,588		)	(198,147		)
	Interest income	2,265			3,517			3,373
	Income tax benefit	55,291			216,550			549,996
	Depreciation, depletion and amortization	(750,776		)	(865,021		)	(1,037,575		)
	Amortization of acquired intangibles, net	(39,206		)	(5,056		)	70,338
	Net loss	$	(874,961	)	$	(1,113,498	)	$	(2,437,148	)
Schedule of Total Assets and Goodwill	The following table presents total assets and goodwill:
		Total Assets									Goodwill, net
		December 31,			December 31,			December 31,			December 31,			December 31,		December 31,
		2014			2013			2012			2014			2013		2012
	Eastern Coal Operations	$	8,648,678		$	9,566,687		$	10,691,029		$	—		$	308,651	$	561,753
	Western Coal Operations	657,971			645,175			647,292			—			—		—
	All Other	1,429,499			1,587,396			1,751,485			—			—		5,912
	Total	$	10,736,148		$	11,799,258		$	13,089,806		$	—		$	308,651	$	567,665

Guarantor_and_NonGuarantor_Inf1

Guarantor and Non-Guarantor Information Guarantor and Non-Guarantor Information (Tables)	12 Months Ended
	Dec. 31, 2014
Supplemental Guarantor and Non-Guarantor Financial Information [Abstract]
Schedule of Condensed Consolidating Balance Sheets [Table Text Block]
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Balance Sheet
	December 31, 2014
		Parent			Guarantor			Non-Guarantor			Eliminations			Total
		(Issuer)			Subsidiaries			Subsidiaries						Consolidated
	Assets
	Current assets:
	Cash and cash equivalents	$	830		$	738,700		$	1,656		$	—		$	741,186
	Trade accounts receivable, net	—			43,784			270,231			—			314,015
	Inventories, net	—			237,945			—			—			237,945
	Short-term marketable securities	—			405,169			—			—			405,169
	Prepaid expenses and other current assets	—			175,221			2,778			—			177,999
	Total current assets	830			1,600,819			274,665			—			1,876,314
	Property, equipment and mine development costs, net	—			1,425,667			—			—			1,425,667
	Owned and leased mineral rights and land, net	—			6,916,307			—			—			6,916,307
	Other acquired intangibles, net	—			97,169			—			—			97,169
	Other non-current assets	8,142,716			8,363,729			14,329			(16,100,083		)	420,691
	Total assets	$	8,143,546		$	18,403,691		$	288,994		$	(16,100,083	)	$	10,736,148
	Liabilities and Stockholders’ Equity
	Current liabilities:
	Current portion of long-term debt	$	49,752		$	128,499		$	—		$	—		$	178,251
	Trade accounts payable	—			215,972			126			—			216,098
	Accrued expenses and other current liabilities	3,130			611,833			237			—			615,200
	Total current liabilities	52,882			956,304			363			—			1,009,549
	Long-term debt	3,678,449			41,070			—			—			3,719,519
	Pension and postretirement medical benefit obligations	—			1,236,986			—			—			1,236,986
	Asset retirement obligations	—			538,008			—			—			538,008
	Deferred income taxes	—			773,466			—			—			773,466
	Other non-current liabilities	1,425,415			1,630,041			267,195			(2,850,831		)	471,820
	Total liabilities	5,156,746			5,175,875			267,558			(2,850,831		)	7,749,348
	Stockholders’ Equity
	Total stockholders’ equity	2,986,800			13,227,816			21,436			(13,249,252		)	2,986,800
	Total liabilities and stockholders’ equity	$	8,143,546		$	18,403,691		$	288,994		$	(16,100,083	)	$	10,736,148
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Balance Sheet
	December 31, 2013
		Parent						Non-Guarantor			Eliminations			Total
		(Issuer)			Guarantor			Subsidiaries						Consolidated
					Subsidiaries
	Assets
	Current assets:
	Cash and cash equivalents	$	467		$	617,952		$	1,225		$	—		$	619,644
	Trade accounts receivable, net	—			287,655			—			—			287,655
	Inventories, net	—			304,863			—			—			304,863
	Short-term marketable securities	—			337,069			—			—			337,069
	Prepaid expenses and other current assets	—			436,352			2,841			—			439,193
	Total current assets	467			1,983,891			4,066			—			1,988,424
	Property, equipment and mine development costs, net	—			1,798,648			—			—			1,798,648
	Owned and leased mineral rights and land, net	—			7,157,506			—			—			7,157,506
	Goodwill, net	—			308,651			—			—			308,651
	Other acquired intangibles, net	—			158,465			—			—			158,465
	Other non-current assets	8,602,537			8,786,932			13,826			(17,015,731		)	387,564
	Total assets	$	8,603,004		$	20,194,093		$	17,892		$	(17,015,731	)	$	11,799,258
	Liabilities and Stockholders’ Equity
	Current liabilities:
	Current portion of long-term debt	$	6,250		$	22,919		$	—		$	—		$	29,169
	Trade accounts payable	—			234,951			—			—			234,951
	Accrued expenses and other current liabilities	3,130			975,365			200			—			978,695
	Total current liabilities	9,380			1,233,235			200			—			1,242,815
	Long-term debt	3,222,906			175,528			—			—			3,398,434
	Pension and postretirement medical benefit obligations	—			990,124			—			—			990,124
	Asset retirement obligations	—			728,575			—			—			728,575
	Deferred income taxes	—			901,552			—			—			901,552
Other non-current liabilities	1,298,852			1,764,744			—			(2,597,704		)	465,892
Total liabilities	4,531,138			5,793,758			200			(2,597,704		)	7,727,392
Stockholders’ Equity
Total stockholders’ equity	4,071,866			14,400,335			17,692			(14,418,027		)	4,071,866
Total liabilities and stockholders’ equity	$	8,603,004		$	20,194,093		$	17,892		$	(17,015,731	)	$	11,799,258
Schedule of Condensed Consolidating Statements of Operations [Table Text Block]
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Statement of Operations
	Year Ended December 31, 2014
		Parent						Non-Guarantor			Eliminations			Total
		(Issuer)			Guarantor			Subsidiaries						Consolidated
					Subsidiaries
	Revenues:
	Coal revenues	$	—		$	3,724,441		$	—		$	—		$	3,724,441
	Freight and handling revenues	—			480,841			—			—			480,841
	Other revenues	—			78,431			3,365			—			81,796
	Total revenues	—			4,283,713			3,365			—			4,287,078
	Costs and expenses:
	Cost of coal sales (exclusive of items shown separately below)	—			3,381,075			—			—			3,381,075
	Freight and handling costs	—			480,841			—			—			480,841
	Other expenses	—			67,412			—			—			67,412
	Depreciation, depletion and amortization	—			750,776			—			—			750,776
	Amortization of acquired intangibles, net	—			39,206			—			—			39,206
	Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)	—			150,111			1,995			—			152,106
	Asset impairment and restructuring	—			24,872			—			—			24,872
	Goodwill impairment	—			308,651			—			—			308,651
	Total costs and expenses	—			5,202,944			1,995			—			5,204,939
	Income (loss) from operations	—			(919,231		)	1,370			—			(917,861		)
	Other income (expense):
	Interest expense	(286,703		)	(1,139		)	(624		)	—			(288,466		)
	Interest income	—			520			1,745			—			2,265
	Gain on sale of marketable equity securities	—			17,883			—			—			17,883
	Loss on early extinguishment of debt	(1,630		)	(392		)	—			—			(2,022		)
	Gain on exchange of equity method investment	—			256,330			—			—			256,330
	Miscellaneous income (expense), net	—			1,770			(151		)	—			1,619
	Total other income (expense), net	(288,333		)	274,972			970			—			(12,391		)
	Income (loss) before income taxes and equity in earnings of investments in Issuer and Guarantor Subsidiaries	(288,333		)	(644,259		)	2,340			—			(930,252		)
	Income tax benefit (expense)	112,450			(56,245		)	(914		)	—			55,291
	Equity in earnings of investments in Issuer and Guarantor Subsidiaries	(699,078		)	—			—			699,078			—
	Net income (loss)	$	(874,961	)	$	(700,504	)	$	1,426		$	699,078		$	(874,961	)
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Statement of Operations
	Year Ended December 31, 2013
		Parent						Non-Guarantor			Eliminations			Total
		(Issuer)			Guarantor			Subsidiaries						Consolidated
					Subsidiaries
	Revenues:
	Coal revenues	$	—		$	4,257,981		$	—		$	—		$	4,257,981
	Freight and handling revenues	—			557,846			—			—			557,846
	Other revenues	—			132,074			5,607			—			137,681
	Total revenues	—			4,947,901			5,607			—			4,953,508
	Costs and expenses:
	Cost of coal sales (exclusive of items shown separately below)	—			3,980,744			—			—			3,980,744
	Freight and handling costs	—			557,846			—			—			557,846
	Other expenses	—			165,485			—			—			165,485
	Depreciation, depletion and amortization	—			865,021			—			—			865,021
	Amortization of acquired intangibles, net	—			5,056			—			—			5,056
	Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)	—			156,155			2,832			—			158,987
	Asset impairment and restructuring	—			37,273			—			—			37,273
	Goodwill impairment	—			253,102			—			—			253,102
	Total costs and expenses	—			6,020,682			2,832			—			6,023,514
	Income from operations	—			(1,072,781		)	2,775			—			(1,070,006		)
	Other income (expense):
	Interest expense	(232,194		)	(13,213		)	(1,181		)	—			(246,588		)
	Interest income	—			3,463			54			—			3,517
	Loss on early extinguishment of debt	(30,139		)	(8,967		)	(1,358		)	—			(40,464		)
	Miscellaneous income (expense), net	—			23,573			(80		)	—			23,493
	Total other expense, net	(262,333		)	4,856			(2,565		)	—			(260,042		)
	Loss before income taxes and equity in earnings of investments in Issuer and Guarantor Subsidiaries	(262,333		)	(1,067,925		)	210			—			(1,330,048		)
Income tax benefit (expense)	102,310			114,322			(82		)	—			216,550
Equity in earnings of investments in Issuer and Guarantor Subsidiaries	(953,475		)	—			—			953,475			—
Net income (loss)	$	(1,113,498	)	$	(953,603	)	$	128		$	953,475		$	(1,113,498	)
Alpha Natural Resources, Inc. and Subsidiaries
Supplemental Condensed Consolidating Statement of Operations
Year Ended December 31, 2012
	Parent						Non-Guarantor			Eliminations			Total
	(Issuer)			Guarantor			Subsidiaries						Consolidated
				Subsidiaries
Revenues:
Coal revenues	$	—		$	6,015,696		$	—		$	—		$	6,015,696
Freight and handling revenues	—			761,928			—			—			761,928
Other revenues	—			184,017			13,243			—			197,260
Total revenues	—			6,961,641			13,243			—			6,974,884
Costs and expenses:
Cost of coal sales (exclusive of items shown separately below)	—			5,004,516			—			—			5,004,516
Freight and handling costs	—			761,928			—			—			761,928
Other expenses	—			45,432			—			—			45,432
Depreciation, depletion and amortization	—			1,037,575			—			—			1,037,575
Amortization of acquired intangibles, net	—			(70,338		)	—			—			(70,338		)
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)	—			205,156			4,632			—			209,788
Asset impairment and restructuring	—			1,068,906			—			—			1,068,906
Goodwill impairment	—			1,713,526			—			—			1,713,526
Total costs and expenses	—			9,766,701			4,632			—			9,771,333
Income (loss) from operations	—			(2,805,060		)	8,611			—			(2,796,449		)
Other income (expense):
Interest expense	(170,111		)	(25,063		)	(2,973		)	—			(198,147		)
Interest income	—			3,347			26			—			3,373
Gain on early extinguishment of debt	—			773			—			—			773
Miscellaneous expense, net	—			3,349			(43		)	—			3,306
Total other expense, net	(170,111		)	(17,594		)	(2,990		)	—			(190,695		)
Income (loss) before income taxes and equity in earnings of investments in Issuer and Guarantor Subsidiaries	(170,111		)	(2,822,654		)	5,621			—			(2,987,144		)
Income tax benefit (expense)	66,343			485,845			(2,192		)	—			549,996
Equity in earnings of investments in Issuer and Guarantor Subsidiaries	(2,333,380		)	—			—			2,333,380			—
Net income (loss)	$	(2,437,148	)	$	(2,336,809	)	$	3,429		$	2,333,380		$	(2,437,148	)
Schedule of Condensed Consolidating Statement of Comprehensive Income (Loss) [Table Text Block]
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Statements of Comprehensive Income (Loss)
	For the Year Ended December 31, 2014
		Parent			Guarantor			Non-Guarantor			Eliminations			Total
		(Issuer)			Subsidiaries			Subsidiaries						Consolidated
	Net income (loss)	$	(874,961	)	$	(700,504	)	$	1,426		$	699,078		$	(874,961	)
	Total comprehensive income (loss)	$	(1,109,514	)	$	(935,057	)	$	1,426		$	933,631		$	(1,109,514	)
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Statements of Comprehensive Income (Loss)
	For the Year Ended December 31, 2013
		Parent			Guarantor			Non-Guarantor			Eliminations			Total
		(Issuer)			Subsidiaries			Subsidiaries						Consolidated
	Net income (loss)	$	(1,113,498	)	$	(953,603	)	$	128		$	953,475		$	(1,113,498	)
	Total comprehensive income (loss)	$	(1,004,048	)	$	(844,153	)	$	128		$	844,025		$	(1,004,048	)
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Statements of Comprehensive Income (Loss)
	For the Year Ended December 31, 2012
		Parent			Guarantor			Non-Guarantor			Eliminations			Total
		(Issuer)			Subsidiaries			Subsidiaries						Consolidated
	Net income (loss)	$	(2,437,148	)	$	(2,336,809	)	$	3,429		$	2,333,380		$	(2,437,148	)
	Total comprehensive income (loss)	$	(2,401,916	)	$	(2,301,577	)	$	3,429		$	2,298,148		$	(2,401,916	)
Schedule of Condensed Consolidating Statements of Cash Flows [Table Text Block]
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2014
		Parent						Non-Guarantor			Total
		(Issuer)			Guarantor			Subsidiaries			Consolidated
					Subsidiaries
	Net cash (used in) provided by operating activities	$	—		$	(284,022	)	$	163		$	(283,859	)
	Investing activities:
	Capital expenditures	—			(185,038		)	—			(185,038		)
	Acquisition of mineral rights under federal lease	—			(42,130		)	—			(42,130		)
	Purchases of marketable securities	—			(679,394		)	—			(679,394		)
	Sales of marketable securities	—			697,929			—			697,929
	Proceeds from sale of property, plant and equipment	—			93,033			—			93,033
	Proceeds from the sale of equity method investments, net	—			112,232			—			112,232
	Other, net	—			1,717			—			1,717
	Net cash used in investing activities	—			(1,651		)	—			(1,651		)
	Financing activities:
	Proceeds from borrowings on long-term debt	500,000			—			—			500,000
	Principal repayments of long-term debt	(27,635		)	(9,919		)	—			(37,554		)
	Principal repayments of capital lease obligations	—			(19,475		)	—			(19,475		)
	Debt issuance costs and modification costs	(24,634		)	—			(4,304		)	(28,938		)
	Common stock repurchases	(1,461		)	—			—			(1,461		)
	Other, net	—			(5,520		)	—			(5,520		)
	Transactions with affiliates	(445,907		)	441,335			4,572			—
	Net cash provided by financing activities	363			406,421			268			407,052
	Net increase in cash and cash equivalents	363			120,748			431			121,542
	Cash and cash equivalents at beginning of period	467			617,952			1,225			619,644
	Cash and cash equivalents at end of period	$	830		$	738,700		$	1,656		$	741,186
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2013
		Parent						Non-Guarantor			Total
		(Issuer)			Guarantor			Subsidiaries			Consolidated
					Subsidiaries
	Net cash provided by operating activities	$	—		$	108,904		$	114		$	109,018
	Investing activities:
	Capital expenditures	—			(215,661		)	—			(215,661		)
	Acquisition of mineral rights under federal lease	—			(42,130		)	—			(42,130		)
	Purchases of marketable securities	—			(900,471		)	—			(900,471		)
	Sales of marketable securities	—			857,000			—			857,000
	Proceeds from sale of property and equipment	—			10,605			—			10,605
	Net cash used in investing activities	—			(290,657		)	—			(290,657		)
	Financing activities:
	Proceeds from borrowings on long-term debt	1,306,677			—			—			1,306,677
	Principal repayments on long-term debt	(762,223		)	(414,109		)	—			(1,176,332		)
	Principal repayments of capital lease obligations	—			(16,136		)	—			(16,136		)
	Debt issuance and modification costs	(36,659		)	—			—			(36,659		)
	Common stock repurchases	(1,435		)	—			—			(1,435		)
	Other, net	—			(5,555		)	—			(5,555		)
	Transactions with affiliates	(506,170		)	505,843			327			—
	Net cash provided by financing activities	190			70,043			327			70,560
	Net (decrease) increase in cash and cash equivalents	190			(111,710		)	441			(111,079		)
	Cash and cash equivalents at beginning of period	277			729,662			784			730,723
	Cash and cash equivalents at end of period	$	467		$	617,952		$	1,225		$	619,644
	Alpha Natural Resources, Inc. and Subsidiaries
	Supplemental Condensed Consolidating Statement of Cash Flows
	Year Ended December 31, 2012
		Parent						Non-Guarantor			Total
		(Issuer)			Guarantor			Subsidiaries			Consolidated
					Subsidiaries
	Net cash (used in) provided by operating activities	$	—		$	518,367		$	52		$	518,419
	Investing activities:
	Capital expenditures	—			(402,377		)	—			(402,377		)
Acquisition of mineral rights under federal lease	—			(95,765		)	—			(95,765		)
Purchases of marketable securities	—			(555,096		)	—			(555,096		)
Sales of marketable securities	—			352,112			—			352,112
Purchase of equity method investment	—			(10,100		)	—			(10,100		)
Proceeds from sale of property, plant and equipment	—			38,250			—			38,250
Net cash used in investing activities	—			(672,976		)	—			(672,976		)
Financing activities:
Proceeds from borrowings on long-term debt	494,795			—			—			494,795
Principal repayments on long-term debt	(45,000		)	(115,157		)	—			(160,157		)
Principal repayments of capital lease obligations	—			(6,490		)	—			(6,490		)
Debt issuance and modification costs	(15,767		)	—			(594		)	(16,361		)
Common stock repurchases	(7,507		)	—			—			(7,507		)
Other, net	176			(5,058		)	—			(4,882		)
Transactions with affiliates	(427,033		)	426,703			330			—
Net cash (used in) provided by financing activities	(336		)	299,998			(264		)	299,398
Net increase (decrease) in cash and cash equivalents	(336		)	145,389			(212		)	144,841
Cash and cash equivalents at beginning of period	613			584,273			996			585,882
Cash and cash equivalents at end of period	$	277		$	729,662		$	784		$	730,723

Quarterly_Financial_Informatio1

Quarterly Financial Information (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Schedule of quarterly financial information (unaudited)
		Year Ended December 31, 2014
		First			Second			Third			Fourth
		Quarter			Quarter			Quarter			Quarter(2)
	Total revenues	$	1,111,773		$	1,054,098		$	1,050,592		$	1,070,615
	Net loss (1) (2)	$	(55,698	)	$	(512,627	)	$	(184,975	)	$	(121,661	)
	Basic loss per share	$	(0.25	)	$	(2.32	)	$	(0.84	)	$	(0.55	)
	Diluted loss per share	$	(0.25	)	$	(2.32	)	$	(0.84	)	$	(0.55	)
	(1)	Net loss includes pretax gains on disposals of equity method investments of $250,331 and $5,999 in the first and fourth quarters of 2014, respectively, and pretax asset impairment and restructuring charges of $9,499, $2,590, $11,544 and $1,239 in the first, second, third and fourth quarters of 2014, respectively. Net loss also includes a goodwill impairment charge of $308,651 in the second quarter of 2014.
	(2)	Net loss in the fourth quarter includes certain out of period adjustments for asset retirement obligations related to the first three quarters of 2014 ($6,096) and for the years ended December 31, 2013 and 2012 ($43,570), which decreased net loss by $49,666. These adjustments resulted in a decrease to basic and diluted loss per share of $0.22. See Note 15 for further details.
		Year Ended December 31, 2013
		First			Second Quarter			Third			Fourth
		Quarter						Quarter			Quarter
	Total revenues	$	1,333,591		$	1,335,123		$	1,191,094		$	1,093,700
	Net loss (1)	$	(110,788	)	$	(185,681	)	$	(458,241	)	$	(358,788	)
	Basic loss per share	$	(0.50	)	$	(0.84	)	$	(2.07	)	$	(1.62	)
	Diluted loss per share	$	(0.50	)	$	(0.84	)	$	(2.07	)	$	(1.62	)
	(1)	Net loss includes asset impairment and restructuring charges of $11,076, $11,265, $2,017 and $12,915 in the first, second, third and fourth quarters of 2013, respectively. Net loss also includes goodwill impairment charges of $253,102 in the third quarter of 2013.

Business_and_Basis_of_Presenta1

Business and Basis of Presentation (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 30, 2014
	mine
	employee
Proceeds from Sale of Property, Plant, and Equipment	$93,033	$10,605	$38,250
Gain (Loss) on Disposition of Property Plant Equipment	19,339	-7,851	4,782
Number of surface mines	15
Number of employees	8,900
Percentage of employees affiliated with union	11.00%
AMFIRE Mining Company, LLC [Member]
Disposal Group, Including Discontinued Operation, Consideration				87,159
Proceeds from Sale of Property, Plant, and Equipment	75,134
Number of Mines	10
Number of Preparation Plants and Loadouts	4
Gain (Loss) on Disposition of Property Plant Equipment	$9,777

Summary_of_Significant_Account3

Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash and Cash Equivalents
Maximum term of maturity at the date of purchase to classify investments as cash equivalent (in months)	3 months
Marketable Securities
Maximum term of maturity to classify marketable securities in prepaid expenses and other current assets (in years)	1 year
Minimum term of maturity to classify marketable securities in other non-current assets (in years)	1 year
Trade Accounts Receivable and Allowance for Doubtful Accounts
Allowance for doubtful accounts	$5,701	$6,206
Advanced Mining Royalties
Changes in the allowance for advance mining royalties
Balance at the beginning of the period	27,344	27,802	20,373
Provisions for non-recoupable advance mining royalties	12,767	3,425	8,913
Write-offs of advance mining royalties	-6,339	-3,883	-1,484
Balance at the end of the period	$33,772	$27,344	$27,802

Summary_of_Significant_Account4

Summary of Significant Accounting Policies (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Owned and Leased Mineral Rights
Depletion expense	$230,740	$266,642	$325,999
Minimum | Mobile mining equipment and other fixed assets
Property, Plant and Equipment [Line Items]
Useful life, minimum (in years)	1 year
Maximum | Mobile mining equipment and other fixed assets
Property, Plant and Equipment [Line Items]
Useful life, minimum (in years)	20 years

Summary_of_Significant_Account5

Summary of Significant Accounting Policies (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
	step
Acquired Intangibles
Amortization of assets	$39,206	$5,056	($70,338)
Future net amortization expense related to coal supply agreements
2013	32,304
2014	24,522
2015	5,353
2016	-357
2017	-243
ThereAfter	3,432
Total	65,011
Goodwill
Number of steps involved in goodwill impairment test	2
Other acquired intangibles
Acquired Intangibles
Amortization of assets	61,295	71,867	113,750
Coal Supply Agreements
Acquired Intangibles
Amortization of assets	$22,089	$66,811	$184,088

Mergers_and_Acquisitions_Detai

Mergers and Acquisitions (Details) (Massey Energy Company, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2012	Jun. 01, 2011
Mergers and Acquisitions
Percentage of voting interests acquired		100.00%
Cost of coal sales
Mergers and Acquisitions
Acquisition related expenses	$34,736
Cost of coal sales | Coal inventory
Mergers and Acquisitions
Acquisition related expenses	3,968
Cost of coal sales | Integration activities and employee severance
Mergers and Acquisitions
Acquisition related expenses	1,468
Cost of coal sales | Contractual settlement-related matters
Mergers and Acquisitions
Acquisition related expenses	29,300
Other expenses
Mergers and Acquisitions
Acquisition related expenses	-32,418
Other expenses | Coal contracts
Mergers and Acquisitions
Acquisition related expenses	-32,418
Selling, general and administrative expenses
Mergers and Acquisitions
Acquisition related expenses	11,418
Selling, general and administrative expenses | Integration activities and employee severance
Mergers and Acquisitions
Acquisition related expenses	1,209
Selling, general and administrative expenses | Professional Fees Related to Legal Financing and Integration Services [Member]
Mergers and Acquisitions
Acquisition related expenses	$10,209

Mergers_and_Acquisitions_Detai1

Mergers and Acquisitions (Details 2) (USD $)	3 Months Ended												12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Mergers and Acquisitions
Total revenues as reported	$1,070,615		$1,050,592		$1,054,098		$1,111,773		$1,093,700	$1,191,094	$1,335,123	$1,333,591	$4,287,078	$4,953,508	$6,974,884
Net loss	($121,661)	[1]	($184,975)	[1]	($512,627)	[1]	($55,698)	[1]	($358,788)	($458,241)	($185,681)	($110,788)	($874,961)	($1,113,498)	($2,437,148)
Basic earnings (loss) per share (in dollars per share)	($0.55)		($0.84)		($2.32)		($0.25)		($1.62)	($2.07)	($0.84)	($0.50)	($3.95)	($5.04)	($11.06)
Diluted earnings (loss) per share (in dollars per share)	($0.55)		($0.84)		($2.32)		($0.25)		($1.62)	($2.07)	($0.84)	($0.50)	($3.95)	($5.04)	($11.06)
[1]	Net loss includes pretax gains on disposals of equity method investments of $250,331 and $5,999 in the first and fourth quarters of 2014, respectively, and pretax asset impairment and restructuring charges of $9,499, $2,590, $11,544 and $1,239 in the first, second, third and fourth quarters of 2014, respectively. Net loss also includes a goodwill impairment charge of $308,651 in the second quarter of 2014.

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income - Changes to Accumulated Other Comprehensive Income (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated other comprehensive income (loss) - beginning balance	($57,148)	($166,598)	($201,830)
Other comprehensive income (loss) before reclassifications	-220,121	110,915	41,554
Amounts reclassified from accumulated other comprehensive income (loss)	-14,432	-1,465	-6,322
Accumulated other comprehensive income (loss) - ending balance	-291,701	-57,148	-166,598
Employee benefit costs
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated other comprehensive income (loss) - beginning balance	-59,102	-171,394	-203,229
Other comprehensive income (loss) before reclassifications	-230,708	111,960	27,433
Amounts reclassified from accumulated other comprehensive income (loss)	-1,308	332	4,402
Accumulated other comprehensive income (loss) - ending balance	-291,118	-59,102	-171,394
Cash flow hedges
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated other comprehensive income (loss) - beginning balance	1,941	4,755	1,333
Other comprehensive income (loss) before reclassifications	0	-971	13,812
Amounts reclassified from accumulated other comprehensive income (loss)	-2,341	-1,843	-10,390
Accumulated other comprehensive income (loss) - ending balance	-400	1,941	4,755
Available-for-sale marketable securities
Accumulated Other Comprehensive Income [Roll Forward]
Accumulated other comprehensive income (loss) - beginning balance	13	41	66
Other comprehensive income (loss) before reclassifications	10,587	-74	309
Amounts reclassified from accumulated other comprehensive income (loss)	-10,783	46	-334
Accumulated other comprehensive income (loss) - ending balance	($183)	$13	$41

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Income - Amounts Reclassified from Accumulated Other Comprehensive Income (Details) (USD $)	3 Months Ended												12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Coal revenues													$3,724,441	$4,257,981	$6,015,696
Cost of coal sales													-3,381,075	-3,980,744	-5,004,516
Other revenues													81,796	137,681	197,260
Interest income													2,265	3,517	3,373
Loss before income taxes													-930,252	-1,330,048	-2,987,144
Income tax benefit													55,291	216,550	549,996
Net income (loss)	-121,661	[1]	-184,975	[1]	-512,627	[1]	-55,698	[1]	-358,788	-458,241	-185,681	-110,788	-874,961	-1,113,498	-2,437,148
Amounts reclassifed from accumulated other comprehensive income (loss) | Employee benefit costs
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Amortization of actuarial loss													258	4,561	6,493
Amortization of prior service credit													-4,477	-3,819	-641
Other Comprehensive Income/(Loss), reclassification adjustment from AOCI, pension and other post retirement benefit plans, other, before tax													2,151	-212	1,207
Loss before income taxes													-2,068	530	7,059
Income tax benefit													760	-198	-2,657
Net income (loss)													-1,308	332	4,402
Amounts reclassifed from accumulated other comprehensive income (loss) | Cash flow hedges
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Loss before income taxes													-3,810	-3,087	-16,605
Income tax benefit													1,469	1,244	6,215
Net income (loss)													-2,341	-1,843	-10,390
Amounts reclassifed from accumulated other comprehensive income (loss) | Cash flow hedges | Commodity swaps
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Coal revenues													-4,189	-4,111	-1,865
Cost of coal sales													379	2,777	-10,256
Other revenues													0	-1,865	-4,484
Amounts reclassifed from accumulated other comprehensive income (loss) | Cash flow hedges | Commodity options
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Other revenues													0	112	0
Amounts reclassifed from accumulated other comprehensive income (loss) | Available-for-sale marketable securities
Reclassification Out Of Accumulated Other Comprehensive Income [Line Items]
Interest income													-17,882	76	-534
Income tax benefit													7,099	-30	200
Net income (loss)													($10,783)	$46	($334)
[1]	Net loss includes pretax gains on disposals of equity method investments of $250,331 and $5,999 in the first and fourth quarters of 2014, respectively, and pretax asset impairment and restructuring charges of $9,499, $2,590, $11,544 and $1,239 in the first, second, third and fourth quarters of 2014, respectively. Net loss also includes a goodwill impairment charge of $308,651 in the second quarter of 2014.

Earnings_Per_Share_Details

Earnings Per Share (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Weighted average shares - basic	221,400,658	220,883,103	220,261,555
Weighted average shares- diluted	221,400,658	220,883,103	220,261,555
Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	2.38%	2.38%
Three Point Two Five Percent Convertible Senior Notes [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	3.25%	3.25%
anr_FourPointEightSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyMember [Domain] [Domain] | Convertible Debt [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	4.88%
anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain] | Convertible Debt [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	3.75%	3.75%

Inventories_net_Details

Inventories, net (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Inventory, Net [Abstract]
Raw coal	$38,301	$39,830
Saleable coal	121,590	171,240
Inventory, Supplies, Net of Reserves	78,054	93,793
Total inventories, net	$237,945	$304,863

Marketable_Securities_Details

Marketable Securities (Details) (Available-for-sale Securities [Member], USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Short-term marketable securities
Available-for-sale Debt Securities, Amortized Cost Basis	$405,289	$337,051
Unrealized Gain	18	66
Unrealized Loss	-138	-48
Fair value	405,169	337,069
U.S. treasury and agency securities
Short-term marketable securities
Available-for-sale Debt Securities, Amortized Cost Basis	80,087	81,484
Unrealized Gain	13	17
Unrealized Loss	-7	-4
Fair value	80,093	81,497
Corporate debt securities
Short-term marketable securities
Available-for-sale Debt Securities, Amortized Cost Basis	325,202	255,567
Unrealized Gain	5	49
Unrealized Loss	-131	-44
Fair value	$325,076	$255,572

Prepaid_Expenses_and_Other_Cur2

Prepaid Expenses and Other Current Assets (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid insurance	$11,445		$12,273
Insurance Settlements Receivable, Current	41,283	[1]	195,228	[1]
Notes and other receivables	6,771		10,381
Deferred income taxes - current	54,451		118,757
Deferred long wall move expenses	9,309		10,766
Refundable income taxes	13,532		19,708
Prepaid freight	20,417		26,445
Deposits	8,834		13,671
Other prepaid expenses	11,957		31,964
Prepaid Expense and Other Assets, Current	$177,999		$439,193
[1]	See Note 13.

Marketable_Securities_Details_

Marketable Securities (Details 2) (Other non-current assets, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Long-term marketable securities
Cost	$134,434
Unrealized Gain	4,661
Unrealized Loss	-2,168
Fair value	136,927
Equity Securities [Member]
Long-term marketable securities
Cost	127,001
Unrealized Gain	0
Unrealized Loss	-181
Fair value	126,820
Mutual Funds Held in Rabbi Trusts [Member]
Long-term marketable securities
Cost	7,433	7,261
Unrealized Gain	4,661	3,637
Unrealized Loss	-1,987	-1,568
Fair value	$10,107	$9,330

Marketable_Securities_Marketab

Marketable Securities Marketable Securities (Details 3) (USD $)	3 Months Ended		12 Months Ended			0 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 29, 2014	Dec. 06, 2013
Long-term marketable securities
Equity Method Investment, Realized Gain (Loss) on Disposal	$5,999	$250,331	$256,330	$0	$0
Marketable Securities, Realized Gain (Loss)			17,883	0	0
Alpha Shale Joint Venture [Member]
Long-term marketable securities
Equity Method Investment, Ownership Percentage							50.00%
Equity Method Investment, Total Consideration Received Upon Sale							300,000
Equity Method Investment, Shares Received Upon Sale						9,523,810
Equity Method Investment, Realized Gain (Loss) on Disposal			250,330
Equity securities sold during the period			3,500,000
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds			90,882
Marketable Securities, Realized Gain (Loss)			17,883
Cash [Member] | Alpha Shale Joint Venture [Member]
Long-term marketable securities
Equity Method Investment, Net Sales Proceeds						100,000	100,000
Equity Securities [Member] | Alpha Shale Joint Venture [Member]
Long-term marketable securities
Equity Method Investment, Net Sales Proceeds							$200,000

Property_Equipment_and_Mine_De2

Property, Equipment and Mine Development Costs (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Capital Leased Assets, Gross	$100,540	$92,105
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation	43,940	26,715
Total property, equipment and mine development costs	3,747,111	4,154,073
Less accumulated depreciation, depletion and amortization	2,321,444	2,355,425
Total property, equipment and mine development costs, net	1,425,667	1,798,648
Depreciation and amortization expense	520,036	598,380	711,577
Interest cost capitalized			1,194
Commitments to purchase new equipment	22,381
Plant and mining equipment
Property, Plant and Equipment [Line Items]
Total property, equipment and mine development costs	3,351,521	3,731,282
Mine development
Property, Plant and Equipment [Line Items]
Total property, equipment and mine development costs	281,594	299,334
Office Equipment, Software, and Other [Member]
Property, Plant and Equipment [Line Items]
Total property, equipment and mine development costs	49,784	61,000
Construction in progress
Property, Plant and Equipment [Line Items]
Total property, equipment and mine development costs	$64,212	$62,457

Asset_Impairment_and_Restructu1

Asset Impairment and Restructuring Asset Impairment and Restructuring (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Impaired Intangible Assets and Long-Lived Assets Held and Used [Line Items]
Asset impairment charges		$1,000,453
Severance expenses	15,756	33,856
Restructuring - professional fees and other expenses	9,627	13,636
Restructuring - lease termination costs		13,445
Restructuring - reserve for advanced royalties and deposits	10,000	7,516
Mineral reserves
Impaired Intangible Assets and Long-Lived Assets Held and Used [Line Items]
Impairment by type of long-lived asset		714,580
Property, plant and equipment
Impaired Intangible Assets and Long-Lived Assets Held and Used [Line Items]
Impairment by type of long-lived asset		281,357
Other acquired intangibles
Impaired Intangible Assets and Long-Lived Assets Held and Used [Line Items]
Impairment by type of long-lived asset		4,516
Eastern Coal Operations
Impaired Intangible Assets and Long-Lived Assets Held and Used [Line Items]
Asset impairment charges		994,876
Severance expenses			15,100
Other Asset Impairment Charges			9,772
All Other
Impaired Intangible Assets and Long-Lived Assets Held and Used [Line Items]
Asset impairment charges		5,577
Other Asset Impairment Charges			9,772
All Other | Mineral reserves
Impaired Intangible Assets and Long-Lived Assets Held and Used [Line Items]
Impairment by type of long-lived asset	$1,890

Goodwill_and_Other_Acquired_In2

Goodwill and Other Acquired Intangibles, Net (Details) (USD $)	0 Months Ended				3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Jun. 01, 2014	Aug. 01, 2013	Oct. 31, 2012	Jun. 01, 2012	Jun. 30, 2014	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in goodwill by segment
Goodwill, beginning balance							$3,077,616	$3,083,528
Accumulated impairment losses, beginning balance							-2,768,965	-2,515,863
Goodwill, net, beginning balance							308,651	567,665
Impairments	-308,651	-253,102	-188,194	-1,525,332	-308,651	-253,102	-308,651	-253,102	-1,713,526
Goodwill, ending balance								3,077,616	3,083,528
Accumulated impairment losses, ending balance								-2,768,965	-2,515,863
Goodwill, net							0	308,651	567,665
Goodwill, Written off Related to Sale of Business Unit								-5,912
Goodwill, Period Increase (Decrease)								-259,014
Eastern Coal Operations
Changes in goodwill by segment
Goodwill, beginning balance							3,024,308	3,024,308
Accumulated impairment losses, beginning balance							-2,715,657	-2,462,555
Goodwill, net, beginning balance							308,651	561,753
Impairments	-308,651	-253,102	-188,194	-1,472,024			-308,651	-253,102	-1,660,218
Goodwill, ending balance							3,024,308	3,024,308	3,024,308
Accumulated impairment losses, ending balance							-3,024,308	-2,715,657	-2,462,555
Goodwill, net							0	308,651	561,753
Goodwill, Written off Related to Sale of Business Unit							0
Goodwill, Period Increase (Decrease)							-308,651	-253,102
Western operations
Changes in goodwill by segment
Goodwill, beginning balance								53,308
Accumulated impairment losses, beginning balance								-53,308
Goodwill, net, beginning balance								0
Impairments				-53,308				0	-53,308
Goodwill, ending balance								53,308	53,308
Accumulated impairment losses, ending balance								-53,308	-53,308
Goodwill, net							0	0	0
Goodwill, Period Increase (Decrease)								0
All Other
Changes in goodwill by segment
Goodwill, beginning balance								5,912
Accumulated impairment losses, beginning balance								0
Goodwill, net, beginning balance								5,912
Impairments								0
Goodwill, ending balance								0
Accumulated impairment losses, ending balance								0
Goodwill, net							0	0
Goodwill, Written off Related to Sale of Business Unit								-5,912
Goodwill, Period Increase (Decrease)								($5,912)

Goodwill_and_Other_Acquired_In3

Goodwill and Other Acquired Intangibles, Net (Details 2) (USD $)	0 Months Ended				3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Jun. 01, 2014	Aug. 01, 2013	Oct. 31, 2012	Jun. 01, 2012	Jun. 30, 2014	Sep. 30, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other acquired intangibles
Goodwill impairment	$308,651	$253,102	$188,194	$1,525,332	$308,651	$253,102	$308,651	$253,102	$1,713,526
Acquisition value							-475,582	-581,202
Accumulated amortization							-378,413	-422,737
Total							-97,169	-158,465
Above-market coal supply and transportation agreements
Other acquired intangibles
Acquisition value							-374,509	-479,361
Accumulated amortization							-305,003	-365,448
Total							-69,506	-113,913
Mine permits
Other acquired intangibles
Acquisition value							-101,073	-101,841
Accumulated amortization							-73,410	-57,289
Total							-27,663	-44,552
Below-market coal supply agreements
Other acquired intangibles
Acquisition value							580,327	605,281
Accumulated amortization							548,169	551,035
Total							32,158	54,246
Eastern Coal Operations
Other acquired intangibles
Goodwill impairment	$308,651	$253,102	$188,194	$1,472,024			$308,651	$253,102	$1,660,218

Other_Noncurrent_Assets_Detail

Other Non-current Assets (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Equity Method Investments [Line Items]
Marketable securities - long term	$136,927	$9,330
Unamortized deferred financing costs, net	96,682	94,672
Advance mining royalties, net	51,530	60,310
Virginia tax credit, net	21,469	22,124
Equity method investments (2)	71,224	151,382
Insurance Settlements Receivable, Noncurrent	20,337	24,281
Other	22,522	25,465
Total other non-current assets	$420,691	$387,564
Marcellus gas joint venture with EDF Trading Resources, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	50.00%	50.00%

Accrued_Expenses_and_Other_Cur2

Accrued Expenses and Other Current Liabilities (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Accounts Payable and Accrued Liabilities, Current [Abstract]
Insurance Settlements Receivable, Current	$41,283	[1]	$195,228	[1]
Wages and employee benefits	111,627		117,561
Current portion of asset retirement obligations	102,493		70,851
Taxes other than income taxes	108,504		123,361
Interest payable	45,612		22,321
Current portion of postretirement medical benefit obligations	46,678		46,678
Deferred revenue	27,488		41,250
Litigation	51,280	[2]	447,214	[2]
Other	121,518		109,459
Total accrued expenses and other current liabilities	$615,200		$978,695
[1]	See Note 13.
[2]	The Company has recorded related receivables of $41,283 and $195,228 from insurance coverage and indemnifications in prepaid expenses and other current assets at December 31, 2014 and 2013, respectively.

LongTerm_Debt_Details

Long-Term Debt (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Jun. 01, 2011
In Thousands, unless otherwise specified
Debt Instrument [Line Items]
Debt discount, net	($121,295)	($150,086)
Total long-term debt	3,897,770	3,427,603
Long-term Debt, Current Maturities	178,251	29,169
Long-term debt, net of current portion	3,719,519	3,398,434
9.75% senior notes due 2018
Debt Instrument [Line Items]
Interest rate (as a percent)	9.75%	9.75%
Carrying amount of debt	500,000	500,000
Debt discount, net	-2,221	-3,453
Six Point Zero Zero Percent Senior Notes Due Twenty Nineteen [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	6.00%	6.00%
Carrying amount of debt	800,000	800,000
Total long-term debt	800,000	800,000
Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Debt Instrument [Line Items]
Interest rate (as a percent)	7.50%
Carrying amount of debt	500,000	0
anr_TermLoanDueTwentyTwenty [Member]
Debt Instrument [Line Items]
Carrying amount of debt	614,062	620,313
Debt discount, net	-2,407	-2,853
Total long-term debt	611,655	617,460
Long-term Debt, Current Maturities	6,250	6,250
Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	6.25%	6.25%
Carrying amount of debt	700,000	700,000
Total long-term debt	700,000	700,000
anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Debt Instrument [Line Items]
Debt discount, net	-42,622	-54,781
Other
Debt Instrument [Line Items]
Carrying amount of debt	61,344	73,305
Convertible Debt [Member] | Four Point Eight Seven Five Percent Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	4.88%
Carrying amount of debt	345,000	345,000
Debt discount, net	-72,114	-80,717
Total long-term debt	272,886	264,283
Convertible Debt [Member] | Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Debt Instrument [Line Items]
Interest rate (as a percent)	7.50%
Convertible Debt [Member] | anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Debt Instrument [Line Items]
Interest rate (as a percent)	3.75%	3.75%
Carrying amount of debt	345,000	345,000
Debt discount, net	-42,622	-54,781
Total long-term debt	302,378	290,219
Convertible Debt [Member] | Three Point Two Five Percent Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	3.25%	3.25%
Carrying amount of debt	109,201	128,182	659,063
Debt discount, net	-976	-3,040
Total long-term debt	108,225	125,142
Debt Instrument, Convertible, Carrying Amount of Equity Component	110,375
Convertible Debt [Member] | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member]
Debt Instrument [Line Items]
Interest rate (as a percent)	2.38%	2.38%
Carrying amount of debt	44,458	65,889
Debt discount, net	-955	-5,242
Total long-term debt	43,503	60,647
Debt Instrument, Convertible, Carrying Amount of Equity Component	$69,851

LongTerm_Debt_Details_2

Long-Term Debt (Details 2) (USD $)	12 Months Ended			0 Months Ended	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	22-May-13	Jun. 30, 2013	Sep. 24, 2014	7-May-14	13-May-13	Dec. 18, 2013	Oct. 25, 2012	Jun. 01, 2011	Oct. 02, 2013	Sep. 30, 2014	Sep. 19, 2014
Debt Instrument [Line Items]
Debt and Capital Lease Obligations	$3,897,770,000	$3,427,603,000
Unamortized discount (premium), net	121,295,000	150,086,000
Long-term Debt, Current Maturities	178,251,000	29,169,000
Gain (loss) on early extinguishment of debt	2,022,000	40,464,000	-773,000
Capital Lease Obligations	51,362,000	58,874,000
anr_TermLoanDueTwentyTwenty [Member]
Debt Instrument [Line Items]
Debt and Capital Lease Obligations	611,655,000	617,460,000
Unamortized discount (premium), net	2,407,000	2,853,000
Maximum borrowing capacity				625,000,000
Rate of Amortization of Quarterly Installments				1.00%
Long-term Debt, Current Maturities	6,250,000	6,250,000
Line of Credit Facility, Interest Rate at Period End	3.50%
Commitment fees of unutilized commitments (as a percent)	0.50%
Debt instrument, carrying value	614,062,000	620,313,000
anr_TermLoanDueTwentyTwenty [Member] | Libor [Member]
Debt Instrument [Line Items]
Margin spread on variable rate basis (as a percent)				2.75%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum				0.75%
anr_TermLoanDueTwentyTwenty [Member] | Base Rate
Debt Instrument [Line Items]
Margin spread on variable rate basis (as a percent)				1.75%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum				1.75%
Term Loan Due Twenty Sixteen [Member]
Debt Instrument [Line Items]
Repayments of Lines of Credit				525,000,000
Gain (loss) on early extinguishment of debt		-9,044,000
anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Debt Instrument [Line Items]
Unamortized discount (premium), net	42,622,000	54,781,000
New Senior Notes
Debt Instrument [Line Items]
Debt and Capital Lease Obligations	497,779,000	496,547,000
Repurchase price as a percentage of principal amount	101.00%
Six Point Zero Zero Percent Senior Notes Due Twenty Nineteen [Member]
Debt Instrument [Line Items]
Debt interest rate (as a percent)	6.00%	6.00%
Debt and Capital Lease Obligations	800,000,000	800,000,000
Percentage of senior notes redeemable during first year after initial period	103.00%
Percentage of senior notes redeemable during second year after initial period	101.50%
Percentage of senior notes redeemable during third year after initial period	100.00%
Debt instrument, carrying value	800,000,000	800,000,000
Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member]
Debt Instrument [Line Items]
Debt interest rate (as a percent)	6.25%	6.25%
Debt and Capital Lease Obligations	700,000,000	700,000,000
Percentage of senior notes redeemable during initial period	100.00%
Percentage of senior notes redeemable during first year after initial period	103.13%
Percentage of senior notes redeemable during second year after initial period	102.08%
Percentage of senior notes redeemable during third year after initial period	101.04%
Senior Notes Redemption Price Percentage of Aggregate Principal Amount During Fourth Year after Initial Period	100.00%
Percentage of aggregate principal amount redeemable	35.00%
Percentage of senior notes redeemed during initial period with net cash proceeds from certain equity offerings	106.25%
Amount of the minimum aggregate principal balance remaining outstanding to redeem the 35% of the 2019 Note	65.00%
Debt instrument, carrying value	700,000,000	700,000,000
Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member] | Maximum
Debt Instrument [Line Items]
Period of closing of equity offering, maximum (in days)	0 years 0 months 180 days
9.75% senior notes due 2018
Debt Instrument [Line Items]
Debt interest rate (as a percent)	9.75%	9.75%
Unamortized discount (premium), net	2,221,000	3,453,000
Percentage of senior notes redeemable during initial period	100.00%
Percentage of aggregate principal amount redeemable	35.00%
Amount of the minimum aggregate principal balance remaining outstanding to redeem the 35% of the 2019 Note	65.00%
Debt instrument, carrying value	500,000,000	500,000,000
Senior notes redemption price percentage of aggregate principal amount after first initial period	109.75%
9.75% senior notes due 2018 | Maximum
Debt Instrument [Line Items]
Period of closing of equity offering, maximum (in days)	0 years 0 months 180 days
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Percentage of Extended Maturity Revolver Facility Commitments						75.00%
Maximum borrowing capacity	1,100,000,000
Line of Credit Facility Maximum Borrowing Capacity before Increase				1,000,000,000
Letters of credit	177,249,000	133,975,000
Percentage of Revolver Facility Commitments not extended						25.00%
Borrowing capacity of Revolver Facility Commitments not extended						276,000,000
Percent reduction of Extended Maturity Revolver Facility Commitments						25.00%
Borrowing capacity after reduction of Extended Maturity Revolver Facility Commitments						618,000,000
Fifth Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Repayment percentage of net cash proceeds from assets sales and condemnation events in excess of specified amount	100.00%
Condemnation events calculated as condition for repayment of outstanding loans	1,500,000,000
Percentage of consolidated tangible assets calculated as condition for repayment of outstanding loans (as a percent)	15.00%
Repayment percentage of gross proceeds from intracompany disposals in excess of specified amount	100.00%
Disposal of assets, minimum, calculated as condition for repayment of outstanding loans	500,000,000
Percentage of net cash proceeds calculated as condition for repayment of outstanding loans (as a percent)	100.00%
Minimum Aggregate Principal Amount Subject to Cross-Default Provision	25,000,000
Fourth Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Minimum Liquidity Covenant, Amount	300,000,000
Senior Secured Leverage Ratio				2.5
Minimum Liquidity Covenant, Amount Before Amendment				500,000,000
increase in the amount of additional debt permitted to be incurred							400,000,000
amount of additional debt incurred required to be unsecured or subject to secured second lien							800,000,000
Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Debt Instrument [Line Items]
Debt interest rate (as a percent)	7.50%
Percentage of aggregate principal amount redeemable	35.00%
Amount of the minimum aggregate principal balance remaining outstanding to redeem the 35% of the 2019 Note	65.00%
Repurchase price as a percentage of principal amount	101.00%
Debt instrument, carrying value	500,000,000	0
Senior notes redemption price percentage of aggregate principal amount after first initial period	107.50%
A/R Facility
Debt Instrument [Line Items]
Letters of credit	34,969,000
Four Point Eight Seven Five Percent Convertible Senior Notes [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Conversion Price	$9.34
anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain] | Convertible Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Conversion Price	$10.10
Convertible Debt [Member] | anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Debt Instrument [Line Items]
Debt instrument principal amount per share	1
Debt interest rate (as a percent)	3.75%	3.75%
Debt Instrument, Interest Rate, Effective Percentage		8.49%
Debt and Capital Lease Obligations	302,378,000	290,219,000
Unamortized discount (premium), net	42,622,000	54,781,000
Aggregate principal amount								345,000,000
Debt instrument, carrying value	345,000,000	345,000,000
Convertible Debt [Member] | Four Point Eight Seven Five Percent Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument principal amount per share	1
Debt interest rate (as a percent)	4.88%
Debt Instrument, Convertible, Conversion Ratio	107.0893
Debt Instrument, Interest Rate, Effective Percentage		9.48%
Debt and Capital Lease Obligations	272,886,000	264,283,000
Unamortized discount (premium), net	72,114,000	80,717,000
Aggregate principal amount									345,000,000
Debt instrument, carrying value	345,000,000	345,000,000
Convertible Debt [Member] | 3.75% and 4.875% Convertible Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Conversion Ratio	99.0589
Convertible Debt [Member] | 3.75% and 4.875% Convertible Notes [Member] | Minimum
Debt Instrument [Line Items]
Covenant required percentage of outstanding principal amount to be held to declare debt instrument due and payable	25.00%
Convertible Debt [Member] | Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Debt Instrument [Line Items]
Debt interest rate (as a percent)	7.50%
Convertible Debt [Member] | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member]
Debt Instrument [Line Items]
Debt interest rate (as a percent)	2.38%	2.38%
Extinguishment of Debt, Amount	21,431,000	3,400,000
Debt Instrument, Convertible, Number of Shares Upon Conversion	18.2962
Debt Instrument, Interest Rate, Effective Percentage	8.64%
Debt and Capital Lease Obligations	43,503,000	60,647,000
Unamortized discount (premium), net	955,000	5,242,000
Debt Instrument, Convertible, Carrying Amount of Equity Component	69,851,000
Debt instrument, carrying value	44,458,000	65,889,000
Debt Instrument, Repurchased Face Amount								181,403,000	36,808,000
Convertible Debt [Member] | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member] | Minimum
Debt Instrument [Line Items]
Covenant required percentage of outstanding principal amount to be held to declare debt instrument due and payable	25.00%
Convertible Debt [Member] | Three Point Two Five Percent Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument principal amount per share	1,000
Debt interest rate (as a percent)	3.25%	3.25%
Extinguishment of Debt, Amount	18,981,000	5,100,000
Debt Instrument, Convertible, Number of Shares Upon Conversion	11.456
Debt Instrument, Interest Rate, Effective Percentage	4.21%
Fair value of long-term debt											730,900,000
Common stock portion of consideration exchanged in acquisition (in shares)	1.025
Cash portion of consideration exchanged in acquisition (in dollars per share)	$10
Debt and Capital Lease Obligations	108,225,000	125,142,000
Unamortized discount (premium), net	976,000	3,040,000
Debt Instrument, Convertible, Carrying Amount of Equity Component	110,375,000
Debt instrument, carrying value	109,201,000	128,182,000									659,063,000
Repurchase amount including interest										115,943,000
Debt Instrument, Repurchased Face Amount								225,787,000	177,093,000	122,511,000
Gain (loss) on early extinguishment of debt			-773,000
Convertible Debt [Member] | Three Point Two Five Percent Convertible Senior Notes [Member] | Minimum
Debt Instrument [Line Items]
Covenant required percentage of outstanding principal amount to be held to declare debt instrument due and payable	25.00%
Convertible Debt [Member] | 2.375% and 3.25% Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Write off of Deferred Debt Issuance Cost		7,425,000
Gain (loss) on early extinguishment of debt	2,022,000	158,000			-22,795,000
Remainder Of Fiscal Year [Member] | Fourth Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Interest Coverage Ratio Before Modification				2.25
Interest Coverage Ratio				1.5
Next Fiscal Year [Member] | Fourth Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Interest Coverage Ratio Before Modification				2.5
Interest Coverage Ratio				1.5
Next Fiscal Year (Year Two) [Member] | Fourth Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Interest Coverage Ratio Before Modification				2.5								2
Interest Coverage Ratio				2								1.25
Next Fiscal Year (Year Three) [Member] | Fourth Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Interest Coverage Ratio Before Modification												2
Interest Coverage Ratio												1.5
ANR Second Receivables Funding, LLC [Member] | A/R Facility
Debt Instrument [Line Items]
Maximum borrowing capacity														200,000,000
Letters of credit	34,969,000
Minimum outstanding principal balance														100,000,000
Line of Credit Facility, Remaining Borrowing Capacity													$165,031,000

LongTerm_Debt_Details_3

Long-Term Debt (Details 3) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Future maturities of long-term debt
2013	$180,177
2014	15,887
2015	363,065
2016	506,676
2017	806,574
Thereafter	2,146,686
Total long-term debt	$4,019,065

Asset_Retirement_Obligations_D

Asset Retirement Obligations (Details) (USD $)	12 Months Ended				3 Months Ended	9 Months Ended
	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Sep. 30, 2014
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount	($51,361,000)
Changes in the asset retirement obligations
Total asset retirement obligations at the beginning of the period	799,426,000		856,701,000			799,426,000
Accretion for the period	47,698,000		60,274,000	65,548,000
Sites added during the period	2,685,000		1,667,000
Revisions in estimated cash flows	-133,680,000	[1]	-74,354,000
Settlement due to sale of asset	-20,108,000
Expenditures for the period	-55,520,000		-44,862,000
Total asset retirement obligations at the end of the period	640,501,000		799,426,000	856,701,000	640,501,000
Less current portion	-102,493,000		-70,851,000		-102,493,000
Long-term portion	538,008,000		728,575,000		538,008,000
Asset Retirement Obligation Revision Of Estimate Related To Changes in Discount Rate	107,263,000		66,521,000
Cost of coal sales
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount	29,987,000
Depreciation Depletion and Amortization [Member]
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount	13,583,000
Net Income (Loss) Available to Common Stockholders, Basic [Member]
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount	-43,570,000				49,666,000
Operating Income (Loss) [Member]
Quantifying Misstatement in Current Year Financial Statements [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount	$43,570,000					$6,096,000
[1]	Amount includes $107,263 and $66,521, primarily related to changes in the discount rate, which were recorded as a reduction to cost of coal sales in the Consolidated Statements of Operations for the years ended December 31, 2014 and 2013, respectively.(2) During the fourth quarter of 2014, the Company discovered a programming logic error in the system used to calculate its asset retirement obligations. The faulty logic caused liability amounts for certain permits in certain circumstances to be miscalculated and the asset retirement obligations related to these permits were overstated in 2013 and 2012. The programming logic was corrected and the Company determined that the errors were immaterial to the Company's financial statements in 2013 and 2012, and therefore, were corrected in the fourth quarter of 2014. The Company corrected these errors by decreasing its asset retirement obligations by $51,361, cost of coal sales by $29,987 and depreciation, depletion and amortization by $13,583 for the year ended December 31, 2014. This resulted in a decrease of $43,570 to loss from operations and net loss for the year ended December 31, 2014.

Other_Noncurrent_Liabilities_D

Other Non-current Liabilities (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2014
Other Liabilities, Noncurrent [Abstract]
Gain (loss) on contract-related matters	($55,454)
Self insured workers’ compensation obligations	142,537	137,824
Black lung obligations	136,457	144,894
Below-market and other contract-related obligations, net (1)	95,885	109,908
Deferred coal revenue	33,138	23,021
Other	57,875	56,173
Total other non-current liabilities	$465,892	$471,820

Fair_Value_of_Financial_Instru2

Fair Value of Financial Instruments and Fair Value Measurements (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Fair value of financial instruments
Long-term debt	$3,719,519		$3,398,434
Debt discount premium, net	121,295		150,086
Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member]
Fair value of financial instruments
Interest rate (as a percent)	6.25%		6.25%
Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Fair value of financial instruments
Interest rate (as a percent)	7.50%
Six Point Zero Zero Percent Senior Notes Due Twenty Nineteen [Member]
Fair value of financial instruments
Interest rate (as a percent)	6.00%		6.00%
9.75% senior notes due 2018
Fair value of financial instruments
Interest rate (as a percent)	9.75%		9.75%
Debt discount premium, net	2,221		3,453
anr_TermLoanDueTwentyTwenty [Member]
Fair value of financial instruments
Debt discount premium, net	2,407		2,853
anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Fair value of financial instruments
Debt discount premium, net	42,622		54,781
Total Fair Value
Fair value of financial instruments
Fair value of long-term debt	1,947,180		3,400,761
Total Fair Value | Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member]
Fair value of financial instruments
Fair value of long-term debt	208,950		602,000
Total Fair Value | Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Fair value of financial instruments
Fair value of long-term debt	320,000
Total Fair Value | Six Point Zero Zero Percent Senior Notes Due Twenty Nineteen [Member]
Fair value of financial instruments
Fair value of long-term debt	240,000		694,872
Total Fair Value | 9.75% senior notes due 2018
Fair value of financial instruments
Fair value of long-term debt	233,430		560,250
Total Fair Value | Term Loan Due Twenty Sixteen [Member]
Fair value of financial instruments
Fair value of long-term debt	499,424		617,291
Carrying Amount
Fair value of financial instruments
Long-term debt	3,836,426		3,354,298
Carrying Amount | Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member]
Fair value of financial instruments
Long-term debt	700,000		700,000
Carrying Amount | Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Fair value of financial instruments
Long-term debt	500,000
Carrying Amount | Six Point Zero Zero Percent Senior Notes Due Twenty Nineteen [Member]
Fair value of financial instruments
Long-term debt	800,000		800,000
Carrying Amount | 9.75% senior notes due 2018
Fair value of financial instruments
Long-term debt	497,779	[1]	496,547	[1]
Carrying Amount | Term Loan Due Twenty Sixteen [Member]
Fair value of financial instruments
Long-term debt	611,655		617,460
Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value
Fair value of financial instruments
Fair value of long-term debt	1,447,756		2,783,470
Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member]
Fair value of financial instruments
Fair value of long-term debt	208,950		602,000
Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Fair value of financial instruments
Fair value of long-term debt	320,000
Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | Six Point Zero Zero Percent Senior Notes Due Twenty Nineteen [Member]
Fair value of financial instruments
Fair value of long-term debt	240,000		694,872
Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | 9.75% senior notes due 2018
Fair value of financial instruments
Fair value of long-term debt	233,430		560,250
Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | Term Loan Due Twenty Sixteen [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Significant Observable Inputs (Level 2) | Total Fair Value
Fair value of financial instruments
Fair value of long-term debt	499,424		617,291
Significant Observable Inputs (Level 2) | Total Fair Value | Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Significant Observable Inputs (Level 2) | Total Fair Value | Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Fair value of financial instruments
Fair value of long-term debt	0
Significant Observable Inputs (Level 2) | Total Fair Value | Six Point Zero Zero Percent Senior Notes Due Twenty Nineteen [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Significant Observable Inputs (Level 2) | Total Fair Value | 9.75% senior notes due 2018
Fair value of financial instruments
Fair value of long-term debt	0		0
Significant Observable Inputs (Level 2) | Total Fair Value | Term Loan Due Twenty Sixteen [Member]
Fair value of financial instruments
Fair value of long-term debt	499,424		617,291
Significant Unobservable Inputs (Level 3) | Total Fair Value
Fair value of financial instruments
Fair value of long-term debt	0		0
Significant Unobservable Inputs (Level 3) | Total Fair Value | Six Point Two Five Percent Senior Notes Due Twenty Twenty One [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Significant Unobservable Inputs (Level 3) | Total Fair Value | Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Fair value of financial instruments
Fair value of long-term debt	0
Significant Unobservable Inputs (Level 3) | Total Fair Value | Six Point Zero Zero Percent Senior Notes Due Twenty Nineteen [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Significant Unobservable Inputs (Level 3) | Total Fair Value | 9.75% senior notes due 2018
Fair value of financial instruments
Fair value of long-term debt	0		0
Significant Unobservable Inputs (Level 3) | Total Fair Value | Term Loan Due Twenty Sixteen [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Convertible Debt [Member] | Seven Point Five Zero Percent Senior Notes Due Twenty Twenty [Member] [Domain]
Fair value of financial instruments
Interest rate (as a percent)	7.50%
Convertible Debt [Member] | Four Point Eight Seven Five Percent Convertible Senior Notes [Member]
Fair value of financial instruments
Interest rate (as a percent)	4.88%
Debt discount premium, net	72,114		80,717
Convertible Debt [Member] | anr_FourPointEightSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyMember [Domain] [Domain]
Fair value of financial instruments
Interest rate (as a percent)	4.88%
Debt discount premium, net	72,114		80,717
Convertible Debt [Member] | anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Fair value of financial instruments
Interest rate (as a percent)	3.75%		3.75%
Debt discount premium, net	42,622		54,781
Convertible Debt [Member] | Three Point Two Five Percent Convertible Senior Notes [Member]
Fair value of financial instruments
Interest rate (as a percent)	3.25%		3.25%
Debt discount premium, net	976		3,040
Convertible Debt [Member] | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member]
Fair value of financial instruments
Interest rate (as a percent)	2.38%		2.38%
Debt discount premium, net	955		5,242
Convertible Debt [Member] | Total Fair Value | anr_FourPointEightSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyMember [Domain] [Domain]
Fair value of financial instruments
Fair value of long-term debt	125,494		372,606
Convertible Debt [Member] | Total Fair Value | anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Fair value of financial instruments
Fair value of long-term debt	172,500		360,956
Convertible Debt [Member] | Total Fair Value | Three Point Two Five Percent Convertible Senior Notes [Member]
Fair value of financial instruments
Fair value of long-term debt	104,014		126,904
Convertible Debt [Member] | Total Fair Value | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member]
Fair value of financial instruments
Fair value of long-term debt	43,368		65,882
Convertible Debt [Member] | Carrying Amount | anr_FourPointEightSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyMember [Domain] [Domain]
Fair value of financial instruments
Long-term debt	272,886		264,283
Convertible Debt [Member] | Carrying Amount | anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Fair value of financial instruments
Long-term debt	302,378		290,219
Convertible Debt [Member] | Carrying Amount | Three Point Two Five Percent Convertible Senior Notes [Member]
Fair value of financial instruments
Long-term debt	108,225		125,142
Convertible Debt [Member] | Carrying Amount | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member]
Fair value of financial instruments
Long-term debt	43,503		60,647
Convertible Debt [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | anr_FourPointEightSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyMember [Domain] [Domain]
Fair value of financial instruments
Fair value of long-term debt	125,494		372,606
Convertible Debt [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Fair value of financial instruments
Fair value of long-term debt	172,500		360,956
Convertible Debt [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | Three Point Two Five Percent Convertible Senior Notes [Member]
Fair value of financial instruments
Fair value of long-term debt	104,014		126,904
Convertible Debt [Member] | Quoted Prices in Active Market for Identical Assets (Level 1) | Total Fair Value | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member]
Fair value of financial instruments
Fair value of long-term debt	43,368		65,882
Convertible Debt [Member] | Significant Observable Inputs (Level 2) | Total Fair Value | anr_FourPointEightSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyMember [Domain] [Domain]
Fair value of financial instruments
Fair value of long-term debt	0		0
Convertible Debt [Member] | Significant Observable Inputs (Level 2) | Total Fair Value | anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Fair value of financial instruments
Fair value of long-term debt	0		0
Convertible Debt [Member] | Significant Observable Inputs (Level 2) | Total Fair Value | Three Point Two Five Percent Convertible Senior Notes [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Convertible Debt [Member] | Significant Observable Inputs (Level 2) | Total Fair Value | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Convertible Debt [Member] | Significant Unobservable Inputs (Level 3) | Total Fair Value | anr_FourPointEightSevenFivePercentConvertibleSeniorNotesDueTwentyTwentyMember [Domain] [Domain]
Fair value of financial instruments
Fair value of long-term debt	0		0
Convertible Debt [Member] | Significant Unobservable Inputs (Level 3) | Total Fair Value | anr_ThreePointSevenFivePercentConvertibleSeniorNotesDueTwentySeventeenMember [Domain]
Fair value of financial instruments
Fair value of long-term debt	0		0
Convertible Debt [Member] | Significant Unobservable Inputs (Level 3) | Total Fair Value | Three Point Two Five Percent Convertible Senior Notes [Member]
Fair value of financial instruments
Fair value of long-term debt	0		0
Convertible Debt [Member] | Significant Unobservable Inputs (Level 3) | Total Fair Value | Two Point Three Seven Five Percent Convertible Senior Notes Due Twenty Fifteen [Member]
Fair value of financial instruments
Fair value of long-term debt	$0		$0
[1]	Net of debt discount of $42,622 and $54,781 as of December 31, 2014 and 2013, respectively.

Fair_Value_of_Financial_Instru3

Fair Value of Financial Instruments and Fair Value Measurements (Details 2) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Total Fair Value | Forward coal sales
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	$760	($398)
Total Fair Value | Commodity swaps
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	-23,614	10,403
Total Fair Value | U.S. treasury and agency securities
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	80,093	81,497
Total Fair Value | Mutual Funds Held in Rabbi Trust
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	10,107	9,330
Total Fair Value | Equity Securities [Member]
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	126,820
Total Fair Value | Corporate debt securities
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	325,076	255,572
Quoted Prices in Active Market for Identical Assets (Level 1) | Forward coal sales
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Quoted Prices in Active Market for Identical Assets (Level 1) | Commodity swaps
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Quoted Prices in Active Market for Identical Assets (Level 1) | U.S. treasury and agency securities
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	80,093	81,497
Quoted Prices in Active Market for Identical Assets (Level 1) | Mutual Funds Held in Rabbi Trust
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	10,107	9,330
Quoted Prices in Active Market for Identical Assets (Level 1) | Equity Securities [Member]
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	126,820
Quoted Prices in Active Market for Identical Assets (Level 1) | Corporate debt securities
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Significant Observable Inputs (Level 2) | Forward coal sales
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	760	-398
Significant Observable Inputs (Level 2) | Commodity swaps
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	-23,614	10,403
Significant Observable Inputs (Level 2) | U.S. treasury and agency securities
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Significant Observable Inputs (Level 2) | Mutual Funds Held in Rabbi Trust
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Significant Observable Inputs (Level 2) | Equity Securities [Member]
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0
Significant Observable Inputs (Level 2) | Corporate debt securities
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	325,076	255,572
Significant Unobservable Inputs (Level 3) | Forward coal sales
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Significant Unobservable Inputs (Level 3) | Commodity swaps
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Significant Unobservable Inputs (Level 3) | U.S. treasury and agency securities
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Significant Unobservable Inputs (Level 3) | Mutual Funds Held in Rabbi Trust
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0	0
Significant Unobservable Inputs (Level 3) | Equity Securities [Member]
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	0
Significant Unobservable Inputs (Level 3) | Corporate debt securities
Fair value of assets and liabilities measured on recurring and nonrecurring basis
Total fair value, assets	$0	$0

Derivative_Financial_Instrumen2

Derivative Financial Instruments (Details)	12 Months Ended
	Dec. 31, 2014
Derivative [Line Items]
Percentage of Diesel Fuel to Cost of Coal Sales	6.00%
Commodity swaps | Next Fiscal Year [Member]
Derivative [Line Items]
Swap Agreements, Percentage of Anticipated Diesel Fuel Usage	43.00%
Derivative, Average Forward Price	2.76
Commodity swaps | Next Fiscal Year (Year Two) [Member]
Derivative [Line Items]
Swap Agreements, Percentage of Anticipated Diesel Fuel Usage	5.00%
Derivative, Average Forward Price	2.74

Derivative_Financial_Instrumen3

Derivative Financial Instruments (Details 2) (Not designated as cash flow hedging instruments, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair value of derivative instruments
Total asset derivatives	$1,189	$10,670
Commodity swaps | Prepaid Expenses and Other Current Assets [Member]
Fair value of derivative instruments
Total asset derivatives	429	8,898
Commodity swaps | Other non-current assets
Fair value of derivative instruments
Total asset derivatives	0	1,772
Forward coal sales | Prepaid Expenses and Other Current Assets [Member]
Fair value of derivative instruments
Total asset derivatives	$760	$0

Derivative_Financial_Instrumen4

Derivative Financial Instruments (Details 3) (Not designated as cash flow hedging instruments, USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair value of derivative instruments
Total liability derivatives	$24,043	$665
Commodity swaps | Accrued Expenses and Other Current Liabilities [Member]
Fair value of derivative instruments
Total liability derivatives	21,021	236
Commodity swaps | Other non-current liabilities
Fair value of derivative instruments
Total liability derivatives	3,022	31
Forward coal sales | Accrued Expenses and Other Current Liabilities [Member]
Fair value of derivative instruments
Total liability derivatives	0
Forward coal sales | Other non-current liabilities
Fair value of derivative instruments
Total liability derivatives		$398

Derivative_Financial_Instrumen5

Derivative Financial Instruments (Details 4) (Designated as cash flow hedging instruments, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Gains and losses from derivative instruments
Gain (loss) reclassified from accumulated other comprehensive income (loss) to earnings	$2,341		$1,843		$10,390
Gain (loss) recorded in accumulated other comprehensive income (loss)	0		-971		13,812
Commodity swaps
Gains and losses from derivative instruments
Gain (loss) reclassified from accumulated other comprehensive income (loss) to earnings	2,341	[1],[2]	1,911	[1],[2]	10,390	[1],[2]
Gain (loss) recorded in accumulated other comprehensive income (loss)	0	[1],[2]	-908	[1],[2]	13,831	[1],[2]
Commodity options
Gains and losses from derivative instruments
Gain (loss) reclassified from accumulated other comprehensive income (loss) to earnings	0		-68		0
Gain (loss) recorded in accumulated other comprehensive income (loss)	$0	[1],[2]	($63)	[1],[2]	($19)	[1],[2]
[1]	Net of tax.
[2]	Amounts are recorded in other revenues in the Consolidated Statements of Operations.

Derivative_Financial_Instrumen6

Derivative Financial Instruments (Details 5) (Not designated as cash flow hedging instruments, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Gains and losses from derivative instruments
Gain (loss) recorded in earnings	($25,752)		($6,213)		$3,530
Forward coal sales
Gains and losses from derivative instruments
Gain (loss) recorded in earnings	1,158	[1]	-15,756	[1]	-11,887	[1]
Forward coal purchases
Gains and losses from derivative instruments
Gain (loss) recorded in earnings	0	[1]	4	[1]	15,452	[1]
Commodity swaps
Gains and losses from derivative instruments
Gain (loss) recorded in earnings	-26,910	[2]	9,539	[2]	348	[2]
Commodity options - coal
Gains and losses from derivative instruments
Gain (loss) recorded in earnings	0	[1]	0	[1]	17	[1]
Interest rate swap
Gains and losses from derivative instruments
Gain (loss) recorded in earnings	$0	[3]	$0	[3]	($400)	[3]
[1]	Amounts are recorded as a component of other revenues in the Consolidated Statements of Operations.
[2]	Amounts are recorded as a component of coal revenues, cost of coal sales and other expenses in the Consolidated Statements of Operations.
[3]	Amount is recorded as a component of interest expense in the Consolidated Statements of Operations.

Derivative_Financial_Instrumen7

Derivative Financial Instruments (Details 6) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments and Hedges, Assets [Abstract]
Amount expected to be reclassified, net of tax, to earnings	$509
Changes to accumulated other comprehensive income (loss) related to hedging activities
Net change associated with current year hedging transactions	0	-971	13,812
Less: reclassification adjustment for amounts reclassified to earnings related to settlement of cash flow hedges, net of income tax of $X, $6,215 and $9,571, for the years ended December 31, 2013, 2012 and 2011, respectively	$2,341	$1,843	$10,390

Income_Taxes_Details

Income Taxes (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current tax expense (benefit):
Federal	($15,430)	($3,949)	($1,686)
State	616	-240	6,265
Total current tax expense (benefit)	-14,814	-4,189	4,579
Deferred tax expense (benefit):
Federal	-24,886	-203,560	-482,015
State	-15,591	-8,801	-72,560
Total deferred tax expense (benefit):	-40,477	-212,361	-554,575
Total income tax expense (benefit):
Federal	-40,316	-207,509	-483,701
State	-14,975	-9,041	-66,295
Income tax expense (benefit) from continuing operations	($55,291)	($216,550)	($549,996)

Income_Taxes_Details_2

Income Taxes (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Statutory federal income tax rate (as a percent)	35.00%	35.00%	35.00%
Reconciliation of statutory federal income tax expense to income from continuing operations before income taxes and the actual income tax expense (benefit)
Federal statutory income tax expense (benefit)	($325,588)	($465,517)	($1,045,500)
Increases (reductions) in taxes due to:
Percentage depletion allowance	-28,630	-34,702	-76,252
State taxes, net of federal tax impact	-2,891	-49,523	-25,748
State tax rate and NOL change, net of federal tax benefit	0	-2,524	-8,180
Change in valuation allowances	196,646	207,681	43,885
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount	6,627	5,509	0
Income Tax Reconciliation Nondeductible Expense Fine And Penalties	2,349	14,513	3,996
State apportionment change, net of federal tax impact	-5,811	15,425	-18,654
Non-deductible goodwill impairment	108,028	88,586	572,503
Effective Income Tax Rate Reconciliation, Tax Settlement, Domestic, Amount	-8,090	0	0
Other, net	2,069	4,002	3,954
Income tax expense (benefit) from continuing operations	($55,291)	($216,550)	($549,996)

Income_Taxes_Details_3

Income Taxes (Details 3) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Deferred tax assets
Asset retirement obligations	$236,389	$297,405
Reserves and accruals not currently deductible	80,492	145,870
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits	460,252	374,662
Alternative minimum tax credit carryforwards	208,759	210,742
Goodwill	28,060	31,700
Workers’ compensation obligations	107,557	104,424
Acquired intangibles, net	15,870	6,469
Deferred Tax Assets, Deferred Income	19,095	28,080
Other	47,541	36,101
Net operating loss carryforwards	1,002,863	797,284
Gross deferred tax assets	2,206,878	2,032,737
Less valuation allowance	-563,142	-294,073	-86,392	-41,940
Total net deferred tax assets	1,643,736	1,738,664
Deferred tax liabilities:
Property, equipment and mineral reserves	-2,218,426	-2,367,180
Deferred Tax Liabilities, Other Finite-Lived Assets	8,729	12,201
Other	-43,059	-53,490
Deferred Tax Liabilities, Prepaid Expenses	-43,822	-57,411
Deferred Tax Liabilities, Investment in Noncontrolled Affiliates	48,715	31,177
Total deferred tax liabilities	-2,362,751	-2,521,459
Net deferred tax liability	($719,015)	($782,795)

Income_Taxes_Details_4

Income Taxes (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Break down of the net deferred tax liability
Current asset	$54,451	$118,757
Noncurrent liability	-773,466	-901,552
Net deferred tax liability	-719,015	-782,795
Changes in the valuation allowance
Valuation allowance beginning of period	294,073	86,392	41,940
Increase in valuation allowance not affecting income tax expense	72,423	0	567
Increase in valuation allowance recorded as an increase to income tax expense	196,646	207,681	43,885
Valuation allowance end of period	563,142	294,073	86,392
State
Operating loss carry-forwards
Operating loss carry-forwards	2,377,111
Valuation allowance	1,893,860
Federal
Operating loss carry-forwards
Operating loss carry-forwards	2,598,751
Valuation allowance	$1,296,142

Income_Taxes_Details_5

Income Taxes (Details 5) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2010
Tax credit carryforward
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$269,069
Amount of alternative minimum tax credit-carryforwards	21,469	22,124
Unrecognized Tax Benefits, Income Tax Penalties Accrued	514
Accrued interest expense	313
Reconciliation illustrating the Company's liability for uncertain tax positions
Unrecognized tax benefits - beginning of period	28,741	28,741		28,741
Reduction as a result of settlement with taxing authorities	-26,020	0	0
Unrecognized tax benefits - end of period	2,721	28,741	28,741	28,741
Federal
Tax credit carryforward
Amount of alternative minimum tax credit-carryforwards	208,759
Income Tax Expense (Benefit) [Member]
Tax credit carryforward
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	196,646
Accumulated Defined Benefit Plans Adjustment, Net Unamortized Gain (Loss) [Member]
Tax credit carryforward
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$72,423

Income_Taxes_Income_Taxes_Deta

Income Taxes Income Taxes (Details 6) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	$26,020
Tax Adjustments, Settlements, and Unusual Provisions	-8,090
Settlement with Taxing Authority [Member]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	$2,721

Employee_Benefit_Plans_Details

Employee Benefit Plans (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Threshold Number of Employees for Mandatory Employer Provided Health Insurance	50
Excise tax on employers (as a percent)	40.00%
Company Administered Postretirement Health Care and Life Insurance Benefits
Defined Benefit Plan Disclosure [Line Items]
Impact of PPACA excise tax on employers to the extent that value of their healthcare plans coverage exceeds certain dollar thresholds	$36,599
Increase in obligation as a result of re-measurement	129,270	-84,769
Workers' Compensation and Pneumoconiosis (Black lung)
Defined Benefit Plan Disclosure [Line Items]
Increase in obligation as a result of re-measurement	$7,417	$11,294

Employee_Benefit_Plans_Details1

Employee Benefit Plans (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Amounts recognized in the consolidated balance sheets:
Pension and postretirement medical benefit obligations	($1,236,986)	($990,124)
Employee benefit plans
Deposits	8,834	13,671
Company Administered Postretirement Health Care and Life Insurance Benefits
Change in benefit obligations:
Accumulated benefit obligation-Beginning of period	942,693	1,006,193
Service cost	11,145	13,785	16,408
Interest cost	42,018	40,170	42,122
Actuarial loss (gain)	129,270	-84,769
Benefits paid	-34,977	-32,686
Change in plan provisions	-26,196	0
Accumulated benefit obligation-end of period	1,063,953	942,693	1,006,193
Change in Fair Value of Plan Assets [Roll Forward]
Balance at the beginning of the period	0
Employer contributions	34,977	32,686
Benefits paid	-34,977	-32,686
Balance at the end of the period	0	0
Funded status	-1,063,953	-942,693
Amounts recognized in the consolidated balance sheets:
Current liabilities	46,678	46,678
Pension and postretirement medical benefit obligations	-1,017,275	-896,015
Total amounts recognized in the consolidated balance sheets	1,063,953	942,693
Amounts recognized in accumulated other comprehensive income (loss):
Prior service cost (credit)	-48,048	-24,521
Net actuarial loss	193,559	64,288
Total amounts recognized in accumulated other comprehensive income (loss)	145,511	39,767
Components of net periodic benefit cost
Service cost	11,145	13,785	16,408
Interest cost	42,018	40,170	42,122
Amortization of net actuarial loss (gain)	0	2,872	4,656
Amortization of prior service cost (credit)	-4,477	-3,819	-641
Net periodic benefit cost	48,686	53,008	62,545
Other changes in plan assets and benefit obligations recognized in other comprehensive (loss) income
Current year actuarial (gain) loss	129,270	-84,769	-47,753
Prior service cost (credit) for period	-28,003	0	-44,835
Amortization of net gain (loss)	0	-2,872	-4,656
Amortization of prior service (cost) credit	4,477	3,819	641
Total recognized in other comprehensive (loss) income	105,744	-83,822	-96,603
Total recognized in net periodic benefit cost and other comprehensive income	154,429	-30,815	-34,058
Estimated amount that will be amortized from Accumulated other comprehensive (loss) income into net period benefit cost in 2012
Prior service cost	-4,477
Weighted-average actuarial assumptions used in determining the benefit obligations
Discount rate (as a percent)	3.93%	4.68%
Weighted-average actuarial assumptions used to determine net periodic benefit cost
Discount rate (as a percent)	4.56%	4.18%	4.10%
Weighted-average annual rate of increase in the per capita cost of covered benefits (health care cost trend rate)
Health care cost trend rate assumed for the next year (as a percent)	7.50%
Rate to which the cost trend is assumed to decline (ultimate trend rate) (as a percent)	5.00%
Year that the rate reaches the ultimate trend rate	2020
Effect of one-percentage-point change in assumed health care trend rates
Effect of one percentage point increase on total service and interest cost components	8,250
Effect of one percentage point decrease on total service and interest cost components	-6,646
Effect of one percentage point increase on accumulated postretirement benefit obligation	157,163
Effect of one percentage point decrease on accumulated postretirement benefit obligation	-126,240
Company Administered Defined Benefit Pension Plans
Change in benefit obligations:
Accumulated benefit obligation-Beginning of period	629,379	792,383
Service cost	0	0	0
Interest cost	31,210	29,497	31,990
Actuarial loss (gain)	145,609	-135,832
Benefits paid	-24,311	-23,607
Accumulated benefit obligation-end of period	768,745	629,379	792,383
Change in Fair Value of Plan Assets [Roll Forward]
Balance at the beginning of the period	535,270	561,151
Actual return on plan assets	44,420	27,786
Employer contributions	6,797	3,002	3,736
Benefits paid	-24,311	-23,607
Settlements	-13,142	-33,062
Balance at the end of the period	549,034	535,270	561,151
Funded status	-219,711	-94,109
Amounts recognized in the consolidated balance sheets:
Pension and postretirement medical benefit obligations	-219,711	-94,109
Amounts recognized in accumulated other comprehensive income (loss):
Net actuarial loss	146,866	12,631
Components of net periodic benefit cost
Service cost	0	0	0
Interest cost	31,210	29,497	31,990
Expected return on plan assets	-35,207	-36,199	-38,798
Amortization of net actuarial loss (gain)	10	822	1,837
Settlements gain	2,151	-212	1,207
Net periodic benefit cost	-1,836	-6,092	-3,764
Other changes in plan assets and benefit obligations recognized in other comprehensive (loss) income
Current year actuarial (gain) loss	136,396	-127,419	67,042
Amortization of net gain (loss)	-10	-822	-1,837
Settlements	-2,151	212	-1,207
Total recognized in other comprehensive (loss) income	134,235	-128,029	63,998
Total recognized in net periodic benefit cost and other comprehensive income	132,399	-134,121	60,234
Information applicable to plans with accumulated benefit obligations in excess of plan assets
Projected benefit obligation	768,745	629,379
Accumulated benefit obligation	768,745	629,379
Fair value of plan assets	549,034	535,270
Weighted-average actuarial assumptions used in determining the benefit obligations
Discount rate (as a percent)	4.00%	4.87%
Weighted-average actuarial assumptions used to determine net periodic benefit cost
Discount rate (as a percent)	4.93%	4.21%	4.22%
Expected long-term return on plan assets	6.75%	6.75%	7.25%
Expected long-term return on plan assets to be used in 2013	6.50%
Employee benefit plans
Defined Benefit Plan, Measurement Date	31-Dec-14	31-Dec-13	31-Dec-12
Company Administered Defined Benefit Pension Plans | Maximum
Employee benefit plans
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	2,216
Workers' Compensation and Pneumoconiosis (Black lung)
Change in benefit obligations:
Accumulated benefit obligation-Beginning of period	156,608	145,271
Service cost	2,199	2,708	8,114
Interest cost	7,125	6,577	5,612
Actuarial loss (gain)	7,417	11,294
Benefits paid	-9,010	-9,242
Accumulated benefit obligation-end of period	170,675	156,608	145,271
Change in Fair Value of Plan Assets [Roll Forward]
Balance at the beginning of the period	12,009	3,431
Actual return on plan assets	13	-19
Employer contributions	9,053	17,839
Benefits paid	-9,010	-9,242
Balance at the end of the period	12,065	12,009	3,431
Funded status	-158,610	-144,599
Defined Benefit Plan, Amounts Recognized in Balance Sheet	-158,610	-144,599
Amounts recognized in the consolidated balance sheets:
Current liabilities	13,716	8,142
Pension and postretirement medical benefit obligations	-144,894	-136,457
Total amounts recognized in the consolidated balance sheets	158,610	144,599
Amounts recognized in accumulated other comprehensive income (loss):
Prior service cost (credit)	6,336	0
Net actuarial loss	25,559	18,146
Total amounts recognized in accumulated other comprehensive income (loss)	31,895	18,146
Components of net periodic benefit cost
Service cost	2,199	2,708	8,114
Interest cost	7,125	6,577	5,612
Expected return on plan assets	-257	-87	-52
Amortization of net actuarial loss (gain)	248	868	0
Net periodic benefit cost	9,315	10,066	13,674
Other changes in plan assets and benefit obligations recognized in other comprehensive (loss) income
Current year actuarial (gain) loss	7,661	11,400	-19,154
Prior service cost (credit) for period	6,336	0	0
Amortization of net gain (loss)	-248	-868	0
Total recognized in other comprehensive (loss) income	13,749	10,532	-19,154
Total recognized in net periodic benefit cost and other comprehensive income	23,064	20,598	-5,480
Weighted-average actuarial assumptions used in determining the benefit obligations
Discount rate (as a percent)	3.89%	4.74%
Rate of increase in future compensation (as a percent)	3.00%	3.00%
Weighted-average actuarial assumptions used to determine net periodic benefit cost
Discount rate (as a percent)	4.60%	4.14%	4.14%
Rate of increase in future compensation (as a percent)	3.00%	3.00%	3.00%
Expected long-term return on plan assets	3.00%	3.00%	3.00%
Employee benefit plans
Insurance premium expense	33,321	29,068	42,566
Self-insured workers' compensation claim	149,464	156,726
Current portion of self-insured workers' compensation	11,640	14,189
Self-insured workers' compensation expense	12,186	12,399	3,271
Benefit obligation secured by letters of credit	98,023
Benefit obligation secured by surety bonds	11,204
Deposits	$7,388

Employee_Benefit_Plans_Details2

Employee Benefit Plans (Details 3) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Company Administered Postretirement Health Care and Life Insurance Benefits
Expected future benefit payments for the next ten years
2013	$46,076
2014	51,233
2015	53,748
2016	55,574
2017	56,381
2018-2022	274,273
Total	537,285
Company Administered Defined Benefit Pension Plans
Expected future benefit payments for the next ten years
2013	29,530
2014	30,427
2015	31,830
2016	33,004
2017	34,089
2018-2022	182,079
Total	340,959
Workers' Compensation and Pneumoconiosis (Black lung)
Expected future benefit payments for the next ten years
2013	13,716
2014	8,697
2015	8,905
2016	9,013
2017	9,145
2018-2022	47,698
Total	$97,174

Employee_Benefit_Plans_Details3

Employee Benefit Plans (Details 4) (Company Administered Defined Benefit Pension Plans)	12 Months Ended
	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Percentages 2013	100.00%
Percentage of Plan Assets 2012	100.00%
Equity funds
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Percentages 2013	38.00%
Percentage of Plan Assets 2012	44.00%
Fixed income funds
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Percentages 2013	60.00%
Percentage of Plan Assets 2012	54.00%
Private equity funds / Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Target Allocation Percentages 2013	2.00%
Percentage of Plan Assets 2012	2.00%

Employee_Benefit_Plans_Details4

Employee Benefit Plans (Details 5) (Company Administered Defined Benefit Pension Plans, USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Defined Benefit Plan Disclosure [Line Items]
Total	$549,034	$535,270	$561,151
Total
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	547,101	534,345
Receivable	1,933	925
Total	549,034	535,270
Total | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	211,425	238,699
Total | Fixed income funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	320,574	280,434
Total | Private equity funds / Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,040	5,480
Total | Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10,062	9,732
Quoted Prices in Active Market for Identical Assets (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Quoted Prices in Active Market for Identical Assets (Level 1) | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Quoted Prices in Active Market for Identical Assets (Level 1) | Fixed income funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Quoted Prices in Active Market for Identical Assets (Level 1) | Private equity funds / Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Quoted Prices in Active Market for Identical Assets (Level 1) | Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Significant Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	531,999	519,133
Significant Observable Inputs (Level 2) | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	211,425	238,699
Significant Observable Inputs (Level 2) | Fixed income funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	320,574	280,434
Significant Observable Inputs (Level 2) | Private equity funds / Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Significant Observable Inputs (Level 2) | Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Total	15,102	15,212	15,208
Significant Unobservable Inputs (Level 3) | Equity funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Significant Unobservable Inputs (Level 3) | Fixed income funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Significant Unobservable Inputs (Level 3) | Private equity funds / Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,040	5,480
Total	5,040	5,480	5,608
Significant Unobservable Inputs (Level 3) | Guaranteed insurance contract
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10,062	9,732
Total	$10,062	$9,732	$9,600

Employee_Benefit_Plans_Details5

Employee Benefit Plans (Details 6) (Company Administered Defined Benefit Pension Plans, USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Change in Fair Value of Plan Assets [Roll Forward]
Balance at the beginning of the period			$561,151
Actual return on plan assets:
Balance at the end of the period	549,034	535,270	561,151
Significant Unobservable Inputs (Level 3)
Change in Fair Value of Plan Assets [Roll Forward]
Balance at the beginning of the period	15,212	15,208
Actual return on plan assets:
Relating to assets still held at the reporting date	601	571
Relating to assets sold during the period	177	331
Purchases, sales, and settlements	-888	-898
Balance at the end of the period	15,102	15,212
Significant Unobservable Inputs (Level 3) | Private equity funds / Guaranteed insurance contract
Change in Fair Value of Plan Assets [Roll Forward]
Balance at the beginning of the period	5,480	5,608
Actual return on plan assets:
Relating to assets still held at the reporting date	601	571
Relating to assets sold during the period	177	331
Purchases, sales, and settlements	-1,218	-1,030
Balance at the end of the period	5,040	5,480
Significant Unobservable Inputs (Level 3) | Guaranteed insurance contract
Change in Fair Value of Plan Assets [Roll Forward]
Balance at the beginning of the period	9,732	9,600
Actual return on plan assets:
Relating to assets still held at the reporting date	0	0
Relating to assets sold during the period	0	0
Purchases, sales, and settlements	330	132
Balance at the end of the period	$10,062	$9,732

Employee_Benefit_Plans_Details6

Employee Benefit Plans (Details 7) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Contribution and Profit Sharing Plans
Total contribution	$680	$48,327	$79,257
Self-Insured Medical Plan
Total claim expense	176,204	199,257	219,707
Multiemployer postretirement benefit plan
Multi-Employer Pension Plans
Expense relative to premium paid	802	1,392	1,540
Obligation to pay retiree medical benefits secured by letters of credit	8,249
Certain subsidiaries | Multiemployer pension plan
Multi-Employer Pension Plans
Period of projected accumulated funding deficiency in the 1974 Plan (in years)	6 years
Expense incurred related to the 1974 plan	$19,204	$21,282	$23,102
Number of the Company's subsidiaries contributing more than 5% to the plan	2
Certain subsidiaries | Multiemployer pension plan | Maximum
Multi-Employer Pension Plans
Funded percentage of the 1974 Plan	80.00%
Certain subsidiaries | Multiemployer pension plan | Minimum
Multi-Employer Pension Plans
Percentage of the total contributions to the 1974 Plan by two of the entity's wholly-owned subsidiaries, Cumberland Coal Resources, LP and Emerald Coal Resources, LP	5.00%

StockBased_Compensation_Awards2

Stock-Based Compensation Awards (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	22-May-13
	stockbasedaward
Share-based Compensation Arrangement
Number of common shares repurchased to satisfy employees' minimum statutory withholdings	311,437	178,195	441,923
Treasury Stock Acquired, Average Cost Per Share	$4.69	$8.05	$16.99
Number of Types of Awards	3
Long-term Incentive Plan 2012 [Member]
Share-based Compensation Arrangement
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized				3,100,000
Common stock shares authorized for issuance of awards	13,100,000
Common stock shares available for grant	4,188,180

StockBased_Compensation_Awards3

Stock-Based Compensation Awards (Details 2) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock-Based Compensation Awards
Document Period End Date	31-Dec-14
Stock-based compensation expense	$27,371	$25,873	$9,881
Total excess tax benefit recognized for stock-based compensation	$0	$0	$0
Selling, General and Administrative Expenses [Member]
Stock-Based Compensation Awards
Percentage of allocated stock-based compensation expense	77.00%	78.00%	51.00%

StockBased_Compensation_Awards4

Stock-Based Compensation Awards (Details 3) (USD $)	12 Months Ended			0 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 22, 2012
	stockbasedaward
Share-based Compensation Arrangement
Treasury Stock Acquired, Average Cost Per Share	$4.69	$8.05	$16.99
Number of Types of Awards	3
Restricted Stock [Member]
Share - based compensation, aggregate disclosures
Fair value of awards vested	$0	$0	$11,142
Performance-based Restricted Cash Unit [Member]
Share-based Compensation Arrangement
Awards outstanding (in shares)	2,744,280
Number of Shares
Non-vested shares outstanding at beginning of the period	0
Vested (in shares)	0
Forfeited/Expired (in shares)	-12,692
Non-vested shares outstanding at end of the period	2,744,280
Weighted Average Grant Date Fair Value
Non-vested shares outstanding at beginning of the period (in dollars per share)	$0
Granted (in dollars per share)	$4.33
Vested (in dollars per share)	$0
Forfeited/Expired (in dollars per share)	$3.37
Non-vested shares outstanding at end of the period (in dollars per share)	$1.67
Share - based compensation, aggregate disclosures
Awards outstanding (in shares)	2,744,280
Performance-based Restricted Cash Unit [Member] | Maximum
Share-based Compensation Arrangement
Awards granted (in shares)	2,756,972
Number of Shares
Granted (in shares)	2,756,972
Time-based Restricted Cash Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)	2,077,491
Awards outstanding (in shares)	1,919,680
Number of Shares
Non-vested shares outstanding at beginning of the period	0
Granted (in shares)	2,077,491
Vested (in shares)	-98,335
Forfeited/Expired (in shares)	-59,476
Non-vested shares outstanding at end of the period	1,919,680
Weighted Average Grant Date Fair Value
Non-vested shares outstanding at beginning of the period (in dollars per share)	$0
Granted (in dollars per share)	$4.38
Vested (in dollars per share)	$2.46
Forfeited/Expired (in dollars per share)	$2.28
Non-vested shares outstanding at end of the period (in dollars per share)	$1.67
Share - based compensation, aggregate disclosures
Unrecognized compensation cost non-vested awards	1,906
Weighted average period for recognition (in years)	2 years 1 month 24 days
Awards outstanding (in shares)	1,919,680
Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Vesting period (in years)	3 years
Awards granted (in shares)	1,632,824
Awards outstanding (in shares)	3,768,433	3,099,289
Number of Shares
Non-vested shares outstanding at beginning of the period	3,099,289
Granted (in shares)	1,632,824
Vested (in shares)	-906,424
Forfeited/Expired (in shares)	-57,256
Non-vested shares outstanding at end of the period	3,768,433	3,099,289
Weighted Average Grant Date Fair Value
Non-vested shares outstanding at beginning of the period (in dollars per share)	$11.66
Granted (in dollars per share)	$4.25
Vested (in dollars per share)	$16.26
Forfeited/Expired (in dollars per share)	$10.34
Non-vested shares outstanding at end of the period (in dollars per share)	$7.32	$11.66
Share - based compensation, aggregate disclosures
Fair value of awards vested	4,470	4,536	13,775
Unrecognized compensation cost non-vested awards	6,833
Weighted average period for recognition (in years)	1 year 5 months 12 days
Awards outstanding (in shares)	3,768,433	3,099,289
Performance Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Vesting period (in years)	3 years
Awards outstanding (in shares)	7,818,631
Number of Shares
Non-vested shares outstanding at beginning of the period	5,566,158
Vested (in shares)	-11,027
Forfeited/Expired (in shares)	-493,472
Non-vested shares outstanding at end of the period	7,818,631
Weighted Average Grant Date Fair Value
Non-vested shares outstanding at beginning of the period (in dollars per share)	$15.25
Granted (in dollars per share)	$4.33
Vested (in dollars per share)	$2.60
Forfeited/Expired (in dollars per share)	$58.60
Non-vested shares outstanding at end of the period (in dollars per share)	$8.78
Share - based compensation, aggregate disclosures
Awards outstanding (in shares)	7,818,631
Performance Based Restricted Share Units [Member] | Minimum
Share-based Compensation Arrangement
Percentage of targeted amount	0.00%
Performance Based Restricted Share Units [Member] | Maximum
Share-based Compensation Arrangement
Percentage of targeted amount	200.00%
Awards granted (in shares)	2,756,972
Number of Shares
Granted (in shares)	2,756,972
Awarded in 2014 [Member] [Member] | Performance-based Restricted Cash Unit [Member]
Share-based Compensation Arrangement
Number of shares issued	1,378,486
Awards outstanding (in shares)	1,372,140
Number of Shares
Non-vested shares outstanding at end of the period	1,372,140
Share - based compensation, aggregate disclosures
Unrecognized compensation cost non-vested awards	0
Awards outstanding (in shares)	1,372,140
Awarded in 2014 [Member] [Member] | Performance Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)	1,378,486
Awards outstanding (in shares)	1,372,140
Number of Shares
Granted (in shares)	1,378,486
Non-vested shares outstanding at end of the period	1,372,140
Share - based compensation, aggregate disclosures
Unrecognized compensation cost non-vested awards	4,194
Weighted average period for recognition (in years)	2 years 0 months 0 days
Awards outstanding (in shares)	1,372,140
Awarded in 2013 [Member] | Performance Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)	1,531,787
Awards outstanding (in shares)	1,497,482
Number of Shares
Granted (in shares)	1,531,787
Non-vested shares outstanding at end of the period	1,497,482
Share - based compensation, aggregate disclosures
Unrecognized compensation cost non-vested awards	6,475
Weighted average period for recognition (in years)	1 year
Awards outstanding (in shares)	1,497,482
Awarded in 2012 [Member] | Performance Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)		1,149,392
Awards outstanding (in shares)	1,044,659
Number of Shares
Granted (in shares)		1,149,392
Non-vested shares outstanding at end of the period	1,044,659
Share - based compensation, aggregate disclosures
Awards outstanding (in shares)	1,044,659
Awarded in 2009 [Member] | Performance Based Restricted Share Units [Member]
Share - based compensation, aggregate disclosures
Fair value of awards vested				4,937
Long-term Incentive Plan 2010 [Member] | Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards outstanding (in shares)	199,733
Number of Shares
Non-vested shares outstanding at end of the period	199,733
Share - based compensation, aggregate disclosures
Awards outstanding (in shares)	199,733
Long-term Incentive Plan 2010 [Member] | Awarded in 2012 [Member] | Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)		706,564
Number of Shares
Granted (in shares)		706,564
Stock And Incentive Compensation Plan 2006 [Member] | Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards outstanding (in shares)	62,161
Number of Shares
Non-vested shares outstanding at end of the period	62,161
Share - based compensation, aggregate disclosures
Awards outstanding (in shares)	62,161
Stock And Incentive Compensation Plan 2006 [Member] | Awarded in 2012 [Member] | Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)		146,044
Number of Shares
Granted (in shares)		146,044
Long-term Incentive Plan 2012 [Member] | Time-based Restricted Cash Units [Member]
Share-based Compensation Arrangement
Awards outstanding (in shares)	1,919,680
Number of Shares
Non-vested shares outstanding at end of the period	1,919,680
Share - based compensation, aggregate disclosures
Awards outstanding (in shares)	1,919,680
Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent	$1,305
Long-term Incentive Plan 2012 [Member] | Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards outstanding (in shares)	3,413,160
Number of Shares
Non-vested shares outstanding at end of the period	3,413,160
Share - based compensation, aggregate disclosures
Awards outstanding (in shares)	3,413,160
Long-term Incentive Plan 2012 [Member] | Awarded in 2014 [Member] [Member] | Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)	1,632,824
Number of Shares
Granted (in shares)	1,632,824
Long-term Incentive Plan 2012 [Member] | Awarded in 2013 [Member] | Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)		1,752,075
Number of Shares
Granted (in shares)		1,752,075
Long-term Incentive Plan 2012 [Member] | Awarded in 2012 [Member] | Time Based Restricted Share Units [Member]
Share-based Compensation Arrangement
Awards granted (in shares)			1,016,733
Number of Shares
Granted (in shares)			1,016,733
Stock Compensation Plan [Member] | Awarded in 2014 [Member] [Member] | Time-based Restricted Cash Units [Member]
Share-based Compensation Arrangement
Number of shares issued	2,077,491

StockBased_Compensation_Awards5

Stock-Based Compensation Awards (Details 4) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement
One-time charge for stock-based compensation	$27,371	$25,873	$9,881
Non-Qualified Stock Options
Share-based Compensation Arrangement
Outstanding and exercisable (in shares)	586,722
Stock option activity
Outstanding at the beginning of the period (in shares)	937,977
Exercised (in shares)	0
Forfeited/Expired (in shares)	-351,255
Outstanding at the end of the period (in shares)	586,722	937,977
Exercisable at the end of the period (in shares)	586,722
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per shares)	$21.77
Exercised (in dollars per shares)	$0
Forfeited/Expired (in dollars per share)	$15.58
Outstanding at the end of the period (in dollars per shares)	$25.48	$21.77
Exercisable at the end of the period (in dollars per shares)	$25.48
Weighted-Average Remaining Contractual Term (Years)
Outstanding at the end of the period (in years)	3 years 4 months 28 days
Exercisable at the end of the period (in years)	3 years 4 months 28 days
Other disclosures
Aggregate intrinsic value of options outstanding and exercisable	0
Cash received from the exercise of awards	0	0	176
Total intrinsic value of awards exercised	$0	$0	$253

StockBased_Compensation_Awards6

Stock-Based Compensation Awards (Details 5) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Options Outstanding and Exercisable
Excess Tax Benefit from Share-based Compensation, Financing Activities	$0	$0	$0
Exercise Price, $11.15 - $20.44
Share-based Compensation Arrangement
Exercise price, low end of range (in dollars per share)	$11.15
Exercise price, high end of range (in dollars per share)	$20.44
Exercise Price, $23.93 - $34.76
Share-based Compensation Arrangement
Exercise price, low end of range (in dollars per share)	$23.93
Exercise price, high end of range (in dollars per share)	$34.76
Exercise Price, $40.82 - $48.26
Share-based Compensation Arrangement
Exercise price, low end of range (in dollars per share)	$40.98
Exercise price, high end of range (in dollars per share)	$48.26
Employee Stock Option [Member]
Options Outstanding and Exercisable
Shares	586,722
Weighted-Average Remaining Life (in years)	3 years 4 months 28 days
Weighted-Average Exercise Price (in dollars per share)	$25.48
Employee Stock Option [Member] | Exercise Price, $11.15 - $20.44
Options Outstanding and Exercisable
Shares	278,429
Weighted-Average Remaining Life (in years)	2 years 4 months 20 days
Weighted-Average Exercise Price (in dollars per share)	$17.42
Employee Stock Option [Member] | Exercise Price, $23.93 - $34.76
Options Outstanding and Exercisable
Shares	199,518
Weighted-Average Remaining Life (in years)	3 years 6 months 7 days
Weighted-Average Exercise Price (in dollars per share)	$28.29
Employee Stock Option [Member] | Exercise Price, $40.82 - $48.26
Options Outstanding and Exercisable
Shares	108,775
Weighted-Average Remaining Life (in years)	5 years 10 months 17 days
Weighted-Average Exercise Price (in dollars per share)	$41.04

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Aggregate future minimum non-cancelable lease payments under operating leases
2013	$5,282
2014	793
2015	150
2016	0
2017	0
Thereafter	0
Total future minimum non-cancelable lease payments under operating leases	6,225
Aggregate future minimum royalties under coal leases
2013	38,494
2014	35,192
2015	33,669
2016	25,546
2017	13,450
Thereafter	65,215
Total future minimum royalties under coal leases	211,566
Total rent expense	25,895	44,087	81,021
Coal royalty expense	214,599	222,875	336,068
Future minimum lease payments under capital leases
2013	19,311
2014	12,067
2015	9,966
2016	3,057
2017	2,962
Thereafter	48,479
Total minimum lease payments	95,842
Less: Amount representing interest (rates range from 2.13% to 13.86%)	-44,480
Present value of net minimum lease payments	51,362
Lower range of interest rate on interest included in minimum lease payments	0.15%
Upper range of interest rate on interest included in minimum lease payments	13.86%
Guarantor Obligations [Line Items]
Long-term Purchase Commitment, Amount	16,478
Unrecorded Unconditional Purchase Obligation, Due within Two Years	64,961
Unrecorded Unconditional Purchase Obligation, Due within Three Years	17,540
Unrecorded Unconditional Purchase Obligation, Due within Four Years	12,930
Unrecorded Unconditional Purchase Obligation, Due within Five Years	66,120
Unrecorded Unconditional Purchase Obligation, Due after Five Years	213,056
Surety bonds
Guarantor Obligations [Line Items]
Amount of guarantee exposure	$676,149

Commitments_and_Contingencies_2

Commitments and Contingencies (Details 2) (USD $)

0 Months Ended

1 Months Ended

3 Months Ended

12 Months Ended

0 Months Ended

1 Months Ended

0 Months Ended

3 Months Ended

0 Months Ended

23-May-14

Aug. 31, 2012

Sep. 30, 2011

Nov. 30, 2010

Aug. 31, 2002

Aug. 29, 2013

Dec. 31, 2014

Dec. 31, 2013

Dec. 31, 2012

Oct. 19, 2012

Dec. 06, 2011

Apr. 05, 2010

Jun. 03, 2014

Feb. 25, 2014

Apr. 29, 2010

Jun. 17, 2014

Jul. 31, 2011

Mar. 05, 2014

Dec. 31, 2012

Jul. 16, 2012

9-May-12

Mar. 20, 2012

Mar. 31, 2014

Apr. 05, 2012

Mar. 01, 2012

Jan. 31, 2012

Jun. 30, 2014

Apr. 15, 2010

Tons

Installments

case

Installment

Miner

Miner

Miner

case

environmental_group

case

case

environmental_group

Subsidiary

Family

Subsidiary

Plaintiffs

Tons

Subsidiary

Subsidiary

Loss Contingencies [Line Items]

Proven and probable coal reserves under federal coal lease (in tons)

222,000,000

130,200,000

Proven and probable coal reserves lease bid

$143,415,000

Number of annual installments

5

Annual installments of lease payments

28,683,000

Lease bid payment at closing

17,392,000

Remaining number of annual installments

4

Annual lease payments under LBA

42,130,000

Number of annual payments on debt instrument

4

Debt Instrument, Annual Principal Payment

3,946,000

Repayments of Long-term Debt

37,554,000

1,176,332,000

160,157,000

Gain (loss) on contract-related matters

-55,454,000

Loss Contingency [Abstract]

Loss Contingency, Range of Possible Loss, Portion Not Accrued

100,000,000

(Income) expense recognized in period

-11,604,000

212,233,000

15,406,000

Number of seriously injured employees filing personal injury claims

2

Compensatory and Punitive Damages Awarded

50,000,000

Compensatory Damages Sought by Plaintiff

44,000,000

Loss Contingency, Damages Awarded, Value

5,000,000

Litigation Settlement Interest

1,120,000

Alpha Appalachia Holdings, Inc. (Formerly Massey)

Loss Contingency [Abstract]

Number of additional putative class actions

2

Number Of Subsidiaries Included In Lawsuits

2

2

Damages

118,500,000

Amount of guarantee exposure

150,000,000

Indemnity receivable included in prepaid expenses and other current assets

38,500,000

Accrued liability included in accrued expenses and other current liabilities

38,500,000

Damage From Explosion at Upper Big Branch Mine

Loss Contingency [Abstract]

Number of miners killed in explosion

29

Number of miners injured in explosion

2

Number of miners whose estates have filed an action

3

Federal Securities Class Action

Loss Contingency [Abstract]

Number of consolidated purported class actions

2

Damages

235,000,000

30,000,000

Loss Contingency, Receivable

70,000,000

Derivative Litigation and Related Class Action Litigation

Loss Contingency [Abstract]

Number of plaintiffs

3

Compensatory and Economic Damages | Alpha Appalachia Holdings, Inc. (Formerly Massey)

Loss Contingency [Abstract]

Damages

38,500,000

38,500,000

Compensatory and Economic Damages | DRIH Corporation [Member]

Loss Contingency [Abstract]

Damages

32,000,000

Punitive Damages | Alpha Appalachia Holdings, Inc. (Formerly Massey)

Loss Contingency [Abstract]

Damages

240,000,000

320,000,000

Punitive Damages | Appalachia Holding [Member]

Loss Contingency [Abstract]

Damages

48,000,000

Mine Water Discharge Suits

Loss Contingency [Abstract]

Number Of Subsidiaries Allegedly Violating Terms Of Water Discharge Permits

2

2

Number of subsidiaries included in partial summary judgment

1

1

Loss Contingency, Claims Settled, Number

3

Loss Contingency, Damages Paid, Value

350

Number of Environmental Groups which Filed Citizens Suit Against Company

2

3

3

3

Damages

27,500,000

Wrongful Death and Personal Injury | Alpha Appalachia Holdings, Inc. (Formerly Massey)

Loss Contingency [Abstract]

Number of families of the deceased miners filing wrongful death suits

20

Number Of Families Of Deceased Miners

29

Number of seriously injured employees filing personal injury claims

2

Number of employees who filed lawsuits against the Company's subsidiary alleging emotional distress or personal injuries

39

Number of Settlements With Families of Deceased Miners

29

Number of Settlements With Seriously Injured Employees

2

Number of settlements with employees who filed lawsuits

39

Number of Families of Deceased Miner Filing Class Action Suits

1

Note Payable for Federal Coal Lease [Member]

Loss Contingencies [Line Items]

Other Notes Payable

3,469,000

Senior Secured Revolving Credit Facility [Member]

Loss Contingency [Abstract]

Letters of Credit Outstanding, Amount

177,249,000

133,975,000

A/R Facility

Loss Contingency [Abstract]

Letters of Credit Outstanding, Amount

$34,969,000

Concentration_of_Credit_Risk_a1

Concentration of Credit Risk and Major Customers (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Total revenues | Concentration of risk by customer | Ten largest customers
Concentration of Credit Risk and Major Customers
Percentage of risk concentration	45.00%	43.00%	42.00%
Total revenues | Concentration of risk by customer | Largest customer
Concentration of Credit Risk and Major Customers
Percentage of risk concentration	8.00%	9.00%	9.00%
Steam coal sales volume | Concentration of risk by product
Concentration of Credit Risk and Major Customers
Percentage of risk concentration	78.00%	77.00%	81.00%
Metallurgical coal sales volume | Concentration of risk by product
Concentration of Credit Risk and Major Customers
Percentage of risk concentration	22.00%	23.00%	19.00%
Accounts Receivable [Member] | Concentration of risk by customer
Concentration of Credit Risk and Major Customers
Percentage of risk concentration	10.00%
Concentration Risk, Customer	2

Segment_Information_Details

Segment Information (Details)	12 Months Ended
	Dec. 31, 2014
	mine
	segment
Segment Reporting [Abstract]
Number of reportable segments	2
Segment Information
Number of surface mines	15
Eastern Coal Operations
Segment Information
Number of surface mines	13
Number of underground mines	45
Western Coal Operations
Segment Information
Number of surface mines	2

Segment_Information_Details_2

Segment Information (Details 2) (USD $)	0 Months Ended				3 Months Ended								12 Months Ended
	Jun. 01, 2014	Aug. 01, 2013	Oct. 31, 2012	Jun. 01, 2012	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
													segment
Segment Reporting [Abstract]
Number of reportable segments													2
Segment Information
Restructuring Costs and Asset Impairment Charges													$24,872,000	$37,273,000	$1,068,906,000
Quantifying Misstatement in Current Year Financial Statements, Amount													-51,361,000
Total revenues					1,070,615,000	1,050,592,000	1,054,098,000	1,111,773,000	1,093,700,000	1,191,094,000	1,335,123,000	1,333,591,000	4,287,078,000	4,953,508,000	6,974,884,000
Depreciation, depletion, and amortization													750,776,000	865,021,000	1,037,575,000
Amortization of acquired intangibles, net													39,206,000	5,056,000	-70,338,000
EBITDA from continuing operations													145,931,000	-216,900,000	-1,825,133,000
Capital expenditures													185,038,000	215,661,000	402,377,000
Acquisition of mineral rights under federal lease													42,130,000	42,130,000	95,765,000
Severance expenses														15,756,000	33,856,000
Goodwill impairment	308,651,000	253,102,000	188,194,000	1,525,332,000			308,651,000			253,102,000			308,651,000	253,102,000	1,713,526,000
Eastern Coal Operations
Segment Information
Restructuring Costs and Asset Impairment Charges														14,384,000	1,033,979,000
Total revenues													3,803,396,000	4,412,334,000	6,290,289,000
Depreciation, depletion, and amortization													670,520,000	780,120,000	949,064,000
Amortization of acquired intangibles, net													41,149,000	7,916,000	-87,875,000
EBITDA from continuing operations													188,337,000	-44,223,000	-1,807,515,000
Capital expenditures													170,063,000	207,503,000	368,838,000
Acquisition of mineral rights under federal lease													0	0	0
Severance expenses													15,100,000
Other Asset Impairment Charges													9,772,000
Goodwill impairment	308,651,000	253,102,000	188,194,000	1,472,024,000									308,651,000	253,102,000	1,660,218,000
Western Coal Operations
Segment Information
Restructuring Costs and Asset Impairment Charges														-411,000	823,000
Total revenues													443,953,000	487,324,000	611,329,000
Depreciation, depletion, and amortization													59,591,000	54,265,000	62,729,000
Amortization of acquired intangibles, net													-2,119,000	-2,878,000	13,644,000
EBITDA from continuing operations													16,053,000	90,879,000	65,153,000
Capital expenditures													12,562,000	5,369,000	18,082,000
Acquisition of mineral rights under federal lease													42,130,000	42,130,000	95,765,000
Goodwill impairment				53,308,000										0	53,308,000
All Other
Segment Information
Restructuring Costs and Asset Impairment Charges														23,300,000	34,104,000
Total revenues													39,729,000	53,850,000	73,266,000
Depreciation, depletion, and amortization													20,665,000	30,636,000	25,782,000
Amortization of acquired intangibles, net													176,000	18,000	3,893,000
EBITDA from continuing operations													-58,459,000	-263,556,000	-82,771,000
Capital expenditures													2,413,000	2,789,000	15,457,000
Acquisition of mineral rights under federal lease													0	0	0
Other Asset Impairment Charges													9,772,000
Goodwill impairment														0
Depreciation Depletion and Amortization [Member]
Segment Information
Quantifying Misstatement in Current Year Financial Statements, Amount													13,583,000
Depreciation Depletion and Amortization [Member] | Eastern Coal Operations
Segment Information
Quantifying Misstatement in Current Year Financial Statements, Amount					13,583,000
Cost of coal sales
Segment Information
Quantifying Misstatement in Current Year Financial Statements, Amount													29,987,000
Cost of coal sales | Eastern Coal Operations
Segment Information
Quantifying Misstatement in Current Year Financial Statements, Amount					29,987,000
Earnings before Interest Income Taxes Depreciation and Amortization [Member] | Eastern Coal Operations
Segment Information
Quantifying Misstatement in Current Year Financial Statements, Amount					$29,987,000

Segment_Information_Details_3

Segment Information (Details 3) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Information
EBITDA from continuing operations	$145,931	($216,900)	($1,825,133)
Interest expense	-288,466	-246,588	-198,147
Interest income	2,265	3,517	3,373
Income tax benefit	55,291	216,550	549,996
Depreciation, depletion and amortization	-750,776	-865,021	-1,037,575
Amortization of acquired intangibles, net	-39,206	-5,056	70,338
Net loss	-874,961	-1,113,498	-2,437,148
Eastern Coal Operations
Segment Information
EBITDA from continuing operations	188,337	-44,223	-1,807,515
Depreciation, depletion and amortization	-670,520	-780,120	-949,064
Amortization of acquired intangibles, net	-41,149	-7,916	87,875
Western Coal Operations
Segment Information
EBITDA from continuing operations	16,053	90,879	65,153
Depreciation, depletion and amortization	-59,591	-54,265	-62,729
Amortization of acquired intangibles, net	2,119	2,878	-13,644
All Other
Segment Information
EBITDA from continuing operations	-58,459	-263,556	-82,771
Depreciation, depletion and amortization	-20,665	-30,636	-25,782
Amortization of acquired intangibles, net	($176)	($18)	($3,893)

Segment_Information_Details_4

Segment Information (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Total assets and goodwill
Total assets	$10,736,148	$11,799,258	$13,089,806
Goodwill, net	0	308,651	567,665
Export Coal Revenues	1,664,557	2,151,464	2,930,557
Export coal revenues as a percentage of aggregate revenue	39.00%	43.00%	42.00%
Eastern Coal Operations
Total assets and goodwill
Total assets	8,648,678	9,566,687	10,691,029
Goodwill, net	0	308,651	561,753
Western Coal Operations
Total assets and goodwill
Total assets	657,971	645,175	647,292
Goodwill, net	0	0	0
All Other
Total assets and goodwill
Total assets	1,429,499	1,587,396	1,751,485
Goodwill, net	$0	$0	$5,912

Guarantor_and_NonGuarantor_Inf2

Guarantor and Non-Guarantor Information (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	$741,186	$619,644	$730,723	$585,882
Trade accounts receivable, net	314,015	287,655
Inventories, net	237,945	304,863
Available-for-sale Securities, Current	405,169	337,069
Prepaid expenses and other current assets	177,999	439,193
Assets, Current	1,876,314	1,988,424
Property, Plant and Equipment, Net	1,425,667	1,798,648
Mineral Rights	6,916,307	7,157,506
Goodwill, net	0	308,651	567,665
Intangible Assets, Net (Excluding Goodwill)	97,169	158,465
Other non-current assets	420,691	387,564
Total assets	10,736,148	11,799,258	13,089,806
Long-term Debt, Current Maturities	178,251	29,169
Trade accounts payable	216,098	234,951
Accrued expenses and other current liabilities	615,200	978,695
Liabilities, Current	1,009,549	1,242,815
Long-term debt	3,719,519	3,398,434
Pension and postretirement medical benefit obligations	1,236,986	990,124
Asset retirement obligations	538,008	728,575
Deferred income taxes	773,466	901,552
Other non-current liabilities	471,820	465,892
Liabilities	7,749,348	7,727,392
Stockholders' Equity Attributable to Parent	2,986,800	4,071,866	4,967,815	7,375,044
Liabilities and Equity	10,736,148	11,799,258
Parent Company (Issuer)
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	830	467
Trade accounts receivable, net	0	0
Inventories, net	0	0
Available-for-sale Securities, Current	0	0
Prepaid expenses and other current assets	0	0
Assets, Current	830	467
Property, Plant and Equipment, Net	0	0
Mineral Rights	0	0
Goodwill, net		0
Intangible Assets, Net (Excluding Goodwill)	0	0
Other non-current assets	8,142,716	8,602,537
Total assets	8,143,546	8,603,004
Long-term Debt, Current Maturities	49,752	6,250
Trade accounts payable	0	0
Accrued expenses and other current liabilities	3,130	3,130
Liabilities, Current	52,882	9,380
Long-term debt	3,678,449	3,222,906
Pension and postretirement medical benefit obligations	0	0
Asset retirement obligations	0	0
Deferred income taxes	0	0
Other non-current liabilities	1,425,415	1,298,852
Liabilities	5,156,746	4,531,138
Stockholders' Equity Attributable to Parent	2,986,800	4,071,866
Liabilities and Equity	8,143,546	8,603,004
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	738,700	617,952
Trade accounts receivable, net	43,784	287,655
Inventories, net	237,945	304,863
Available-for-sale Securities, Current	405,169	337,069
Prepaid expenses and other current assets	175,221	436,352
Assets, Current	1,600,819	1,983,891
Property, Plant and Equipment, Net	1,425,667	1,798,648
Mineral Rights	6,916,307	7,157,506
Goodwill, net		308,651
Intangible Assets, Net (Excluding Goodwill)	97,169	158,465
Other non-current assets	8,363,729	8,786,932
Total assets	18,403,691	20,194,093
Long-term Debt, Current Maturities	128,499	22,919
Trade accounts payable	215,972	234,951
Accrued expenses and other current liabilities	611,833	975,365
Liabilities, Current	956,304	1,233,235
Long-term debt	41,070	175,528
Pension and postretirement medical benefit obligations	1,236,986	990,124
Asset retirement obligations	538,008	728,575
Deferred income taxes	773,466	901,552
Other non-current liabilities	1,630,041	1,764,744
Liabilities	5,175,875	5,793,758
Stockholders' Equity Attributable to Parent	13,227,816	14,400,335
Liabilities and Equity	18,403,691	20,194,093
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	1,656	1,225
Trade accounts receivable, net	270,231	0
Inventories, net	0	0
Available-for-sale Securities, Current	0	0
Prepaid expenses and other current assets	2,778	2,841
Assets, Current	274,665	4,066
Property, Plant and Equipment, Net	0	0
Mineral Rights	0	0
Goodwill, net		0
Intangible Assets, Net (Excluding Goodwill)	0	0
Other non-current assets	14,329	13,826
Total assets	288,994	17,892
Long-term Debt, Current Maturities	0	0
Trade accounts payable	126	0
Accrued expenses and other current liabilities	237	200
Liabilities, Current	363	200
Long-term debt	0	0
Pension and postretirement medical benefit obligations	0	0
Asset retirement obligations	0	0
Deferred income taxes	0	0
Other non-current liabilities	267,195	0
Liabilities	267,558	200
Stockholders' Equity Attributable to Parent	21,436	17,692
Liabilities and Equity	288,994	17,892
Eliminations
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	0	0
Trade accounts receivable, net	0	0
Inventories, net	0	0
Available-for-sale Securities, Current	0	0
Prepaid expenses and other current assets	0	0
Assets, Current	0	0
Property, Plant and Equipment, Net	0	0
Mineral Rights	0	0
Goodwill, net		0
Intangible Assets, Net (Excluding Goodwill)	0	0
Other non-current assets	-16,100,083	-17,015,731
Total assets	-16,100,083	-17,015,731
Long-term Debt, Current Maturities	0	0
Trade accounts payable	0	0
Accrued expenses and other current liabilities	0	0
Liabilities, Current	0	0
Long-term debt	0	0
Pension and postretirement medical benefit obligations	0	0
Asset retirement obligations	0	0
Deferred income taxes	0	0
Other non-current liabilities	-2,850,831	-2,597,704
Liabilities	-2,850,831	-2,597,704
Stockholders' Equity Attributable to Parent	-13,249,252	-14,418,027
Liabilities and Equity	($16,100,083)	($17,015,731)

Guarantor_and_NonGuarantor_Inf3

Guarantor and Non-Guarantor Information Guarantor and Non-Guarantor Information (Details 2) (USD $)	0 Months Ended				3 Months Ended												12 Months Ended
In Thousands, unless otherwise specified	Jun. 01, 2014	Aug. 01, 2013	Oct. 31, 2012	Jun. 01, 2012	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Coal revenues																	$3,724,441	$4,257,981	$6,015,696
Freight and handling revenues																	480,841	557,846	761,928
Other revenues																	81,796	137,681	197,260
Total revenues					1,070,615		1,050,592		1,054,098		1,111,773		1,093,700	1,191,094	1,335,123	1,333,591	4,287,078	4,953,508	6,974,884
Cost of coal sales (exclusive of items shown separately below)																	3,381,075	3,980,744	5,004,516
Freight and handling costs																	480,841	557,846	761,928
Other expenses																	67,412	165,485	45,432
Depreciation, depletion and amortization																	750,776	865,021	1,037,575
Amortization of acquired intangibles, net																	39,206	5,056	-70,338
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)																	152,106	158,987	209,788
Asset impairment and restructuring					1,239		11,544		2,590		9,499		12,915	2,017	11,265	11,076	24,872	37,273	1,068,906
Goodwill impairment	308,651	253,102	188,194	1,525,332					308,651					253,102			308,651	253,102	1,713,526
Costs and Expenses																	5,204,939	6,023,514	9,771,333
Operating Income (Loss)																	-917,861	-1,070,006	-2,796,449
Interest Expense																	288,466	246,588	198,147
Interest income																	2,265	3,517	3,373
Marketable Securities, Realized Gain (Loss)																	17,883	0	0
(Loss) gain on early extinguishment of debt																	-2,022	-40,464	773
Equity Method Investment, Realized Gain (Loss) on Disposal					5,999						250,331						256,330	0	0
Miscellaneous income, net																	1,619	23,493	3,306
Nonoperating Income (Expense)																	-12,391	-260,042	-190,695
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest																	-930,252	-1,330,048	-2,987,144
Income tax benefit																	55,291	216,550	549,996
Equity in Earnings of Investments in Issuer and Guarantor Subsidiaries																	0	0	0
Net income (loss)					-121,661	[1]	-184,975	[1]	-512,627	[1]	-55,698	[1]	-358,788	-458,241	-185,681	-110,788	-874,961	-1,113,498	-2,437,148
Parent Company (Issuer)
Condensed Financial Statements, Captions [Line Items]
Coal revenues																	0	0	0
Freight and handling revenues																	0	0	0
Other revenues																	0	0	0
Total revenues																	0	0	0
Cost of coal sales (exclusive of items shown separately below)																	0	0	0
Freight and handling costs																	0	0	0
Other expenses																	0	0	0
Depreciation, depletion and amortization																	0	0	0
Amortization of acquired intangibles, net																	0	0	0
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)																	0	0	0
Asset impairment and restructuring																	0	0	0
Goodwill impairment																	0	0	0
Costs and Expenses																	0	0	0
Operating Income (Loss)																	0	0	0
Interest Expense																	286,703	232,194	170,111
Interest income																	0	0	0
Marketable Securities, Realized Gain (Loss)																	0
(Loss) gain on early extinguishment of debt																	-1,630	-30,139	0
Equity Method Investment, Realized Gain (Loss) on Disposal																	0
Miscellaneous income, net																	0	0	0
Nonoperating Income (Expense)																	-288,333	-262,333	-170,111
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest																	-288,333	-262,333	-170,111
Income tax benefit																	112,450	102,310	66,343
Equity in Earnings of Investments in Issuer and Guarantor Subsidiaries																	-699,078	-953,475	-2,333,380
Net income (loss)																	-874,961	-1,113,498	-2,437,148
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Coal revenues																	3,724,441	4,257,981	6,015,696
Freight and handling revenues																	480,841	557,846	761,928
Other revenues																	78,431	132,074	184,017
Total revenues																	4,283,713	4,947,901	6,961,641
Cost of coal sales (exclusive of items shown separately below)																	3,381,075	3,980,744	5,004,516
Freight and handling costs																	480,841	557,846	761,928
Other expenses																	67,412	165,485	45,432
Depreciation, depletion and amortization																	750,776	865,021	1,037,575
Amortization of acquired intangibles, net																	39,206	5,056	-70,338
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)																	150,111	156,155	205,156
Asset impairment and restructuring																	24,872	37,273	1,068,906
Goodwill impairment																	308,651	253,102	1,713,526
Costs and Expenses																	5,202,944	6,020,682	9,766,701
Operating Income (Loss)																	-919,231	-1,072,781	-2,805,060
Interest Expense																	1,139	13,213	25,063
Interest income																	520	3,463	3,347
Marketable Securities, Realized Gain (Loss)																	17,883
(Loss) gain on early extinguishment of debt																	-392	-8,967	773
Equity Method Investment, Realized Gain (Loss) on Disposal																	256,330
Miscellaneous income, net																	1,770	23,573	3,349
Nonoperating Income (Expense)																	274,972	4,856	-17,594
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest																	-644,259	-1,067,925	-2,822,654
Income tax benefit																	-56,245	114,322	485,845
Equity in Earnings of Investments in Issuer and Guarantor Subsidiaries																	0	0	0
Net income (loss)																	-700,504	-953,603	-2,336,809
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Coal revenues																	0	0	0
Freight and handling revenues																	0	0	0
Other revenues																	3,365	5,607	13,243
Total revenues																	3,365	5,607	13,243
Cost of coal sales (exclusive of items shown separately below)																	0	0	0
Freight and handling costs																	0	0	0
Other expenses																	0	0	0
Depreciation, depletion and amortization																	0	0	0
Amortization of acquired intangibles, net																	0	0	0
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)																	1,995	2,832	4,632
Asset impairment and restructuring																	0	0	0
Goodwill impairment																	0	0	0
Costs and Expenses																	1,995	2,832	4,632
Operating Income (Loss)																	1,370	2,775	8,611
Interest Expense																	624	1,181	2,973
Interest income																	1,745	54	26
Marketable Securities, Realized Gain (Loss)																	0
(Loss) gain on early extinguishment of debt																	0	-1,358	0
Equity Method Investment, Realized Gain (Loss) on Disposal																	0
Miscellaneous income, net																	-151	-80	-43
Nonoperating Income (Expense)																	970	-2,565	-2,990
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest																	2,340	210	5,621
Income tax benefit																	-914	-82	-2,192
Equity in Earnings of Investments in Issuer and Guarantor Subsidiaries																	0	0	0
Net income (loss)																	1,426	128	3,429
Eliminations
Condensed Financial Statements, Captions [Line Items]
Coal revenues																	0	0	0
Freight and handling revenues																	0	0	0
Other revenues																	0	0	0
Total revenues																	0	0	0
Cost of coal sales (exclusive of items shown separately below)																	0	0	0
Freight and handling costs																	0	0	0
Other expenses																	0	0	0
Depreciation, depletion and amortization																	0	0	0
Amortization of acquired intangibles, net																	0	0	0
Selling, general and administrative expenses (exclusive of depreciation, depletion and amortization shown separately above)																	0	0	0
Asset impairment and restructuring																	0	0	0
Goodwill impairment																	0	0	0
Costs and Expenses																	0	0	0
Operating Income (Loss)																	0	0	0
Interest Expense																	0	0	0
Interest income																	0	0	0
Marketable Securities, Realized Gain (Loss)																	0
(Loss) gain on early extinguishment of debt																	0	0	0
Equity Method Investment, Realized Gain (Loss) on Disposal																	0
Miscellaneous income, net																	0	0	0
Nonoperating Income (Expense)																	0	0	0
Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest																	0	0	0
Income tax benefit																	0	0	0
Equity in Earnings of Investments in Issuer and Guarantor Subsidiaries																	699,078	953,475	2,333,380
Net income (loss)																	$699,078	$953,475	$2,333,380
[1]	Net loss includes pretax gains on disposals of equity method investments of $250,331 and $5,999 in the first and fourth quarters of 2014, respectively, and pretax asset impairment and restructuring charges of $9,499, $2,590, $11,544 and $1,239 in the first, second, third and fourth quarters of 2014, respectively. Net loss also includes a goodwill impairment charge of $308,651 in the second quarter of 2014.

Guarantor_and_NonGuarantor_Inf4

Guarantor and Non-Guarantor Information Guarantor and Non-Guarantor Information (Details 3) (USD $)	3 Months Ended												12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Net loss	($121,661)	[1]	($184,975)	[1]	($512,627)	[1]	($55,698)	[1]	($358,788)	($458,241)	($185,681)	($110,788)	($874,961)	($1,113,498)	($2,437,148)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent													-1,109,514	-1,004,048	-2,401,916
Parent Company (Issuer)
Condensed Financial Statements, Captions [Line Items]
Net loss													-874,961	-1,113,498	-2,437,148
Comprehensive Income (Loss), Net of Tax, Attributable to Parent													-1,109,514	-1,004,048	-2,401,916
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net loss													-700,504	-953,603	-2,336,809
Comprehensive Income (Loss), Net of Tax, Attributable to Parent													-935,057	-844,153	-2,301,577
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net loss													1,426	128	3,429
Comprehensive Income (Loss), Net of Tax, Attributable to Parent													1,426	128	3,429
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net loss													699,078	953,475	2,333,380
Comprehensive Income (Loss), Net of Tax, Attributable to Parent													$933,631	$844,025	$2,298,148
[1]	Net loss includes pretax gains on disposals of equity method investments of $250,331 and $5,999 in the first and fourth quarters of 2014, respectively, and pretax asset impairment and restructuring charges of $9,499, $2,590, $11,544 and $1,239 in the first, second, third and fourth quarters of 2014, respectively. Net loss also includes a goodwill impairment charge of $308,651 in the second quarter of 2014.

Guarantor_and_NonGuarantor_Inf5

Guarantor and Non-Guarantor Information Guarantor and Non-Guarantor Information (Details 4) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	($283,859)	$109,018	$518,419
Capital expenditures	185,038	215,661	402,377
Acquisition of mineral rights under federal lease	-42,130	-42,130	-95,765
Payments to Acquire Available-for-sale Securities	679,394	900,471	555,096
Sales of marketable securities	697,929	857,000	352,112
Payments to Acquire Equity Method Investments	0	0	-10,100
Proceeds from Sale of Property, Plant, and Equipment	93,033	10,605	38,250
Proceeds from Sale of Equity Method Investments	112,232	0	0
Payments for (Proceeds from) Other Investing Activities	-1,717	0	0
Net Cash Provided by (Used in) Investing Activities	-1,651	-290,657	-672,976
Proceeds from borrowings on long-term debt	500,000	1,306,677	494,795
Repayments of Long-term Debt	37,554	1,176,332	160,157
Repayments of Long-term Capital Lease Obligations	19,475	16,136	6,490
Payments of Debt Issuance Costs	28,938	36,659	16,361
Payments for Repurchase of Common Stock	1,461	1,435	7,507
Other, net	-5,520	-5,555	-4,882
Payments of Distributions to Affiliates	0	0	0
Net cash provided by financing activities	407,052	70,560	299,398
Cash and Cash Equivalents, Period Increase (Decrease)	121,542	-111,079	144,841
Cash Equivalents, at Carrying Value	741,186	619,644	730,723	585,882
Parent Company (Issuer)
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	0	0	0
Capital expenditures	0	0	0
Acquisition of mineral rights under federal lease	0	0	0
Payments to Acquire Available-for-sale Securities	0	0	0
Sales of marketable securities	0	0	0
Payments to Acquire Equity Method Investments			0
Proceeds from Sale of Property, Plant, and Equipment	0	0	0
Proceeds from Sale of Equity Method Investments	0
Payments for (Proceeds from) Other Investing Activities	0
Net Cash Provided by (Used in) Investing Activities	0	0	0
Proceeds from borrowings on long-term debt	500,000	1,306,677	494,795
Repayments of Long-term Debt	27,635	762,223	45,000
Repayments of Long-term Capital Lease Obligations	0	0	0
Payments of Debt Issuance Costs	24,634	36,659	15,767
Payments for Repurchase of Common Stock	1,461	1,435	7,507
Other, net	0	0	176
Payments of Distributions to Affiliates	445,907	506,170	427,033
Net cash provided by financing activities	363	190	-336
Cash and Cash Equivalents, Period Increase (Decrease)	363	190	-336
Cash Equivalents, at Carrying Value	830	467	277	613
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	-284,022	108,904	518,367
Capital expenditures	185,038	215,661	402,377
Acquisition of mineral rights under federal lease	-42,130	-42,130	-95,765
Payments to Acquire Available-for-sale Securities	679,394	900,471	555,096
Sales of marketable securities	697,929	857,000	352,112
Payments to Acquire Equity Method Investments			-10,100
Proceeds from Sale of Property, Plant, and Equipment	93,033	10,605	38,250
Proceeds from Sale of Equity Method Investments	112,232
Payments for (Proceeds from) Other Investing Activities	-1,717
Net Cash Provided by (Used in) Investing Activities	-1,651	-290,657	-672,976
Proceeds from borrowings on long-term debt	0	0	0
Repayments of Long-term Debt	9,919	414,109	115,157
Repayments of Long-term Capital Lease Obligations	19,475	16,136	6,490
Payments of Debt Issuance Costs	0	0	0
Payments for Repurchase of Common Stock	0	0	0
Other, net	-5,520	-5,555	-5,058
Payments of Distributions to Affiliates	-441,335	-505,843	-426,703
Net cash provided by financing activities	406,421	70,043	299,998
Cash and Cash Equivalents, Period Increase (Decrease)	120,748	-111,710	145,389
Cash Equivalents, at Carrying Value	738,700	617,952	729,662	584,273
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	163	114	52
Capital expenditures	0	0	0
Acquisition of mineral rights under federal lease	0	0	0
Payments to Acquire Available-for-sale Securities	0	0	0
Sales of marketable securities	0	0	0
Payments to Acquire Equity Method Investments			0
Proceeds from Sale of Property, Plant, and Equipment	0	0	0
Proceeds from Sale of Equity Method Investments	0
Payments for (Proceeds from) Other Investing Activities	0
Net Cash Provided by (Used in) Investing Activities	0	0	0
Proceeds from borrowings on long-term debt	0	0	0
Repayments of Long-term Debt	0	0	0
Repayments of Long-term Capital Lease Obligations	0	0	0
Payments of Debt Issuance Costs	4,304	0	594
Payments for Repurchase of Common Stock	0	0	0
Other, net	0	0	0
Payments of Distributions to Affiliates	-4,572	-327	-330
Net cash provided by financing activities	268	327	-264
Cash and Cash Equivalents, Period Increase (Decrease)	431	441	-212
Cash Equivalents, at Carrying Value	$1,656	$1,225	$784	$996

Quarterly_Financial_Informatio2

Quarterly Financial Information (Unaudited) (Details) (USD $)	0 Months Ended				3 Months Ended												12 Months Ended			9 Months Ended
	Jun. 01, 2014	Aug. 01, 2013	Oct. 31, 2012	Jun. 01, 2012	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2014
Condensed Income Statements, Captions [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount																	($51,361,000)
Equity Method Investment, Realized Gain (Loss) on Disposal					5,999,000						250,331,000						256,330,000	0	0
Total revenues					1,070,615,000		1,050,592,000		1,054,098,000		1,111,773,000		1,093,700,000	1,191,094,000	1,335,123,000	1,333,591,000	4,287,078,000	4,953,508,000	6,974,884,000
Net loss					-121,661,000	[1]	-184,975,000	[1]	-512,627,000	[1]	-55,698,000	[1]	-358,788,000	-458,241,000	-185,681,000	-110,788,000	-874,961,000	-1,113,498,000	-2,437,148,000
Basic earnings (loss) per share (in dollars per share)					($0.55)		($0.84)		($2.32)		($0.25)		($1.62)	($2.07)	($0.84)	($0.50)	($3.95)	($5.04)	($11.06)
Diluted earnings (loss) per share (in dollars per share)					($0.55)		($0.84)		($2.32)		($0.25)		($1.62)	($2.07)	($0.84)	($0.50)	($3.95)	($5.04)	($11.06)
Asset impairment and restructuring charges					1,239,000		11,544,000		2,590,000		9,499,000		12,915,000	2,017,000	11,265,000	11,076,000	24,872,000	37,273,000	1,068,906,000
Goodwill impairment	308,651,000	253,102,000	188,194,000	1,525,332,000					308,651,000					253,102,000			308,651,000	253,102,000	1,713,526,000
Operating Income (Loss) [Member]
Condensed Income Statements, Captions [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount																	43,570,000			6,096,000
Net Income (Loss) Available to Common Stockholders, Basic [Member]
Condensed Income Statements, Captions [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount					49,666,000												-43,570,000
Earnings per share, basic and diluted [Member]
Condensed Income Statements, Captions [Line Items]
Quantifying Misstatement in Current Year Financial Statements, Amount					($0.22)
[1]	Net loss includes pretax gains on disposals of equity method investments of $250,331 and $5,999 in the first and fourth quarters of 2014, respectively, and pretax asset impairment and restructuring charges of $9,499, $2,590, $11,544 and $1,239 in the first, second, third and fourth quarters of 2014, respectively. Net loss also includes a goodwill impairment charge of $308,651 in the second quarter of 2014.