Arch Resources (ARCH) 10-Q 9 Aug 16 2016 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2016	Aug. 01, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	ARCH COAL INC
Entity Central Index Key	1,037,676
Document Type	10-Q
Document Period End Date	Jun. 30, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		21,293,090

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Revenues	$ 420,298	$ 644,462	$ 848,404	$ 1,321,467
Costs, expenses and other operating
Cost of sales (exclusive of items shown separately below)	419,042	566,252	838,358	1,128,574
Depreciation, depletion and amortization	58,459	97,372	122,158	202,246
Amortization of acquired sales contracts, net	1	(1,644)	(832)	(5,034)
Change in fair value of coal derivatives and coal trading activities, net	1,158	1,211	2,368	2,431
Asset impairment and mine closure costs	43,701	19,146	129,221	19,146
Selling, general and administrative expenses	19,019	24,268	38,845	46,873
Other operating (income) expense, net	(10,561)	7,403	(12,781)	16,489
Total operating expenses	530,819	714,008	1,117,337	1,410,725
Loss from operations	(110,521)	(69,546)	(268,933)	(89,258)
Interest expense, net
Interest expense (contractual interest of $100,767 and $199,332 for the three and six months ended June 30, 2016)	(45,273)	(99,574)	(89,724)	(198,826)
Interest and investment income	933	962	2,071	3,335
Interest expense, net	(44,340)	(98,612)	(87,653)	(195,491)
Loss before nonoperating expenses	(154,861)	(168,158)	(356,586)	(284,749)
Nonoperating expenses
Expenses related to proposed debt restructuring	0	(4,016)	(2,213)	(4,016)
Reorganization items, net	(21,271)	0	(25,146)	0
Nonoperating income (expense)	(21,271)	(4,016)	(27,359)	(4,016)
Loss before income taxes	(176,132)	(172,174)	(383,945)	(288,765)
Benefit from income taxes	(245)	(4,071)	(1,356)	(7,467)
Net loss	$ (175,887)	$ (168,103)	$ (382,589)	$ (281,298)
Net loss per common share
Basic and diluted LPS - Net loss (usd per share)	$ (8.26)	$ (7.90)	$ (17.97)	$ (13.22)
Basic and diluted weighted average shares outstanding (shares)	21,293	21,291	21,293	21,279

Condensed Consolidated Stateme3

Condensed Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2016
Income Statement [Abstract]
Contractual interest	$ 100,767	$ 199,332

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net loss	$ (175,887)	$ (168,103)	$ (382,589)	$ (281,298)
Derivative instruments
Comprehensive income (loss) before tax	(162)	(3,199)	(386)	1,846
Income tax benefit (provision)	0	1,153	81	(664)
Derivatives qualifying as hedges, adjustment, net of tax	(162)	(2,046)	(305)	1,182
Pension, postretirement and other post-employment benefits
Comprehensive income (loss) before tax	(2,749)	3,474	(4,087)	3,768
Income tax benefit (provision)	0	(1,252)	481	(1,357)
Pension and other postretirement benefit plans, adjustment, net of tax	(2,749)	2,222	(3,606)	2,411
Available-for-sale securities
Comprehensive income (loss) before tax	504	68	3,407	359
Income tax benefit (provision)	0	(28)	(1,043)	(132)
Available-for-sale securities adjustment, net of tax	504	40	2,364	227
Total other comprehensive income (loss)	(2,407)	216	(1,547)	3,820
Total comprehensive loss	$ (178,294)	$ (167,887)	$ (384,136)	$ (277,478)

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 269,814	$ 450,781
Short term investments	203,417	200,192
Restricted cash	102,236	97,542
Trade accounts receivable (net of allowance for doubtful accounts of $7.8 million for both periods, respectively.	129,087	117,405
Other receivables	15,377	18,362
Inventories	172,698	196,720
Prepaid royalties	7,737	10,022
Coal derivative assets	4,091	8,035
Other current assets	39,741	39,866
Total current assets	944,198	1,138,925
Property, plant and equipment, net	3,493,553	3,619,029
Other assets
Prepaid royalties	20,997	23,671
Equity investments	163,772	201,877
Other noncurrent assets	62,705	58,379
Total other assets	247,474	283,927
Total assets	4,685,225	5,041,881
Liabilities not subject to compromise
Accounts payable	78,043	128,131
Accrued expenses and other current liabilities	153,028	329,450
Current maturities of debt	0	5,042,353
Total current liabilities	231,071	5,499,934
Long-term debt	0	30,953
Asset retirement obligations	390,634	396,659
Accrued pension benefits	19,853	27,373
Accrued postretirement benefits other than pension	87,286	99,810
Accrued workers’ compensation	118,997	112,270
Other noncurrent liabilities	33,918	119,171
Total liabilities not subject to compromise	881,759	6,286,170
Liabilities subject to compromise	5,430,456	0
Total liabilities	6,312,215	6,286,170
Stockholders' deficit
Common stock, $0.01 par value, authorized 26,000 shares, issued 21,448 shares and 21,446 shares at June 30, 2016 and December 31, 2015, respectively	2,145	2,145
Paid-in capital	3,055,646	3,054,211
Treasury stock, at cost, 152 shares at June 30, 2016 and December 31, 2015	(53,863)	(53,863)
Accumulated deficit	(4,627,556)	(4,244,967)
Accumulated other comprehensive loss	(3,362)	(1,815)
Total stockholders’ deficit	(1,626,990)	(1,244,289)
Total liabilities and stockholders’ deficit	$ 4,685,225	$ 5,041,881

Condensed Consolidated Balance6

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 7.8	$ 7.8
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	26,000,000	26,000,000
Common stock, shares issued	21,448,000	21,446,000
Treasury Stock, Shares	152,000	152,000

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Operating activties
Net loss	$ (382,589)	$ (281,298)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation, depletion and amortization	122,158	202,246
Amortization of acquired sales contracts, net	(832)	(5,034)
Amortization relating to financing activities	7,657	12,539
Prepaid royalties expensed	1,770	3,939
Employee stock-based compensation expense	1,435	3,354
Asset impairment and non-cash mine closure costs	119,194	17,242
Non-cash bankruptcy reorganization items	(14,892)	0
Expenses related to proposed debt restructuring	2,213	4,016
Gains on disposals and divestitures, net	(6,269)	(1,325)
Deferred income taxes	(418)	(7,510)
Changes in:
Receivables	(7,776)	12,433
Inventories	21,152	(33,743)
Accounts payable, accrued expenses and other current liabilities	84,160	(56,419)
Income taxes, net	(937)	(37)
Other	(6,278)	4,022
Cash used in operating activities	(60,252)	(125,575)
Investing activities
Capital expenditures	(74,137)	(99,361)
Additions to prepaid royalties	(217)	(409)
Proceeds from (consideration paid for) disposals and divestitures	(3,303)	991
Purchases of marketable securities	(98,750)	(161,336)
Proceeds from sale or maturity of marketable securities and other investments	94,589	157,729
Investments in and advances to affiliates	(2,890)	(5,138)
Deposits of restricted cash	(4,695)	(37,885)
Cash used in investing activities	(89,403)	(145,409)
Financing activities
Payments on term loan	0	(9,750)
Net payments on other debt	(10,293)	(9,826)
Expenses related to proposed debt restructuring	(2,213)	(4,016)
Debt financing costs	(18,806)	0
Cash used in financing activities	(31,312)	(23,592)
Decrease in cash and cash equivalents	(180,967)	(294,576)
Cash and cash equivalents, beginning of period	450,781	734,231
Cash and cash equivalents, end of period	$ 269,814	$ 439,655

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements include the accounts of Arch Coal, Inc. and its subsidiaries (the “Company”). The Company’s primary business is the production of thermal and metallurgical coal from surface and underground mines located throughout the United States, for sale to utility, industrial and steel producers both in the United States and around the world. The Company currently operates mining complexes in West Virginia, Kentucky, Virginia, Illinois, Wyoming and Colorado. All subsidiaries are wholly-owned. Intercompany transactions and accounts have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial reporting and U.S. Securities and Exchange Commission regulations. In the opinion of management, all adjustments, consisting of normal, recurring accruals considered necessary for a fair presentation, have been included. Results of operations for the three and six months ended June 30, 2016 are not necessarily indicative of results to be expected for the year ending December 31, 2016 . These financial statements should be read in conjunction with the audited financial statements and related notes as of and for the year ended December 31, 2015 included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission. On August 4, 2015 the Company affected a 1-for-10 reverse stock split of its common stock. Each stockholder's percentage ownership and proportional voting power remained unchanged as a result of the reverse stock split. All applicable share data, per share amounts and related information in the Condensed Consolidated Financial Statements and notes thereto have been adjusted retroactively to give effect to the 1-for-10 reverse stock split. Filing Under Chapter 11 of the United States Bankruptcy Code On January 11, 2016 (the “Petition Date”), the Company and substantially all of its wholly owned domestic subsidiaries (the “Filing Subsidiaries” and, together with Arch, the “Debtors”) filed voluntary petitions for reorganization (collectively, the “Bankruptcy Petitions”) under Chapter 11 of Title 11 of the U.S. Code (the “Bankruptcy Code”) in the United States Bankruptcy Court for the Eastern District of Missouri (the “Court”). The Debtor’s Chapter 11 Cases (collectively, the “Chapter 11 Cases”) are being jointly administered under the caption In re Arch Coal, Inc., et al. Case No. 16-40120 (lead case). Each Debtor will continue to operate its business as a “debtor in possession” under the jurisdiction of the Court and in accordance with the applicable provisions of the Bankruptcy Code and the orders of the Court. The filing of the Bankruptcy Petitions constituted an event of default that accelerated the Company's obligations under the documents governing each of its 7.00% senior notes due 2019, 9.875% senior notes due 2019, 8.00% senior secured second lien notes due 2019, 7.25% senior notes due 2020, 7.25% senior notes due 2021 (together, the “senior notes”) and senior secured first lien term loan due 2018 (the “Existing Credit Agreement”) (collectively with the senior notes, the “Debt Instruments”). Immediately after filing the Bankruptcy Petitions, the Company began notifying all known current or potential creditors of the Debtors of the bankruptcy filings. Additionally, on the Petition Date, the New York Stock Exchange (the “NYSE”) determined that the Company's stock was no longer suitable for listing pursuant to Section 8.02.01D of the NYSE continued listing standards and trading in the Company’s common stock was suspended on January 11, 2016. The Company expects that its existing common stock will be extinguished upon the Company's emergence from Chapter 11 and existing equity holders will not receive consideration in respect of their equity interests. On the Petition Date, the Debtors filed a number of motions with the Court generally designed to stabilize their operations and facilitate the Debtors’ transition into Chapter 11. Certain of these motions sought authority from the Court for the Debtors to make payments upon, or otherwise honor, certain pre-petition obligations (e.g., obligations related to certain employee wages, salaries and benefits and certain vendors and other providers essential to the Debtors’ businesses). The Court has entered orders approving the relief sought in these motions, in certain cases on an interim basis. Pursuant to Section 362 of the Bankruptcy Code, the filing of the Bankruptcy Petitions automatically stayed most actions against the Debtors, including actions to collect indebtedness incurred prior to the Petition Date or to exercise control over the Debtors’ property. Subject to certain exceptions under the Bankruptcy Code, the filing of the Debtors’ Chapter 11 Cases also automatically stayed the continuation of most legal proceedings or the filing of other actions against or on behalf of the Debtors or their property to recover on, collect or secure a claim arising prior to the Petition Date or to exercise control over property of the Debtors’ bankruptcy estates, unless and until the Court modifies or lifts the automatic stay as to any such claim. Notwithstanding the general application of the automatic stay described above, governmental authorities may determine to continue actions brought under their police and regulatory powers. As required by the Bankruptcy Code, the U.S. Trustee for the Eastern District of Missouri appointed an official committee of unsecured creditors (the “Creditors’ Committee”) on January 25, 2016. The Creditors’ Committee represents all unsecured creditors of the Debtors and has a right to be heard on all matters that come before the Court. For periods subsequent to filing the Bankruptcy Petitions, the Company will apply the Financial Accounting Standards Board ("FASB") Accounting Standards Codification ("ASC") 852, "Reorganizations", in preparing its consolidated financial statements. ASC 852 requires that financial statements distinguish transactions and events that are directly associated with the reorganization from the ongoing operations of the business. Accordingly, certain revenues, expenses, realized gains and losses and provisions for losses that are realized or incurred in the bankruptcy proceedings have been recorded in a reorganization line item on the Condensed Consolidated Statement of Operations. In addition, the pre-petition obligations that may be impacted by the bankruptcy reorganization process have been classified on the balance sheet as liabilities subject to compromise. These liabilities are reported as the amounts expected to be allowed by the Court, even if they may be settled for lesser amounts. Restructuring Support Agreement As previously disclosed, prior to the Petition Date, certain of the Debtors entered into a Restructuring Support Agreement, dated as of January 10, 2016, which agreement was amended (on February 25, 2016, March 28, 2016, April 26, 2016, May 5, 2016, June 10, 2016 and June 23, 2016). On July 5, 2016, the Debtors entered into an Amended and Restated Restructuring Support Agreement (the “Amended and Restated RSA”) with lenders holding more than 75% of the aggregate principal amount of loans outstanding under Arch’s pre-petition first lien credit facility, the statutory committee of unsecured creditors appointed in the Chapter 11 Cases pursuant to Section 1102 of the Bankruptcy Code (the “Committee”) and certain members of the Committee. See Note 18, "Subsequent Events." Approval of the Disclosure Statement; Solicitation of Votes on the Plan; Confirmation Hearing On July 6, 2016, the Company filed its Third Amended Joint Plan of Reorganization Under Chapter 11 of the Bankruptcy Code (the “Third Amended Plan”) and its Disclosure Statement for the Third Amended Plan. On July 8, 2016, the Court entered an order authorizing the Company to solicit acceptances to the Third Amended Plan, setting a voting deadline of August 31, 2016 and scheduling a Confirmation Hearing with respect to the Third Amended Plan on September 13, 2016. Debtor-In-Possession Financing On January 21, 2016, the Superpriority Secured Debtor-in-Possession Credit Agreement (as amended on March 4, 2016, March 28, 2016, April 26, 2016, June 10, 2016 and June 23, 2016, the “DIP Credit Agreement”) was entered into by and among the Company, as borrower, certain of the Debtors, as guarantors (the “Guarantors” and, together with the Company, the “Loan Parties”), the lenders from time to time party thereto (the “DIP Lenders”) and Wilmington Trust, National Association, as administrative agent and collateral agent for the DIP Lenders (in such capacities, the “DIP Agent”). The DIP Credit Agreement, which has been approved by the Court on a final basis, provides for a super-priority senior secured debtor-in-possession credit facility (the “DIP Facility”) consisting of term loans (collectively, the “DIP Term Loan”) in the aggregate principal amount of up to $275 million . The maturity date of the DIP Facility is the earliest of (i) January 31, 2017, (ii) the date of the substantial consummation of a plan of reorganization that is confirmed pursuant to an order of the Court, (iii) the consummation of the sale of all or substantially all of the assets of the Loan Parties pursuant to Section 363 of the Bankruptcy Code and (iv) the date the obligations under the DIP Facility are accelerated pursuant to the terms of the DIP Credit Agreement. Borrowings under the DIP Facility bear interest at an interest rate per annum equal to, at the Company’s option (i) LIBOR plus 9.00% , subject to a 1.00% LIBOR floor or (ii) the base rate plus 8.00% . At a hearing held on February 23, 2016 in the Chapter 11 Cases, the Court issued an order approving the DIP Facility on a final basis (the "Final Order"), overruling the objections of the Creditors’ Committee and certain other parties who asserted, among other things, that the DIP Facility was unnecessary and argued that the Debtors should enter into an alternate debtor-in-possession financing facility proposed by certain members of the Creditors’ Committee. The Company entered into an amendment to the DIP Credit Agreement, dated as of July 20, 2016. See Note 18, "Subsequent Events." Securitization Agreement On January 13, 2016, the Company agreed with its securitization financing providers (the “Securitization Financing Providers”) that, subject to certain amendments (the “Amendments”), they will continue the $200 million trade accounts receivable securitization facility provided to Arch Receivable Company, LLC, a non-debtor special-purpose entity that is a wholly owned subsidiary of the Company (“Arch Receivable”) (the “Securitization Facility”). Pursuant to the Amendments, which have been approved by the Court on a final basis, the Debtors agreed to a revised schedule of fees payable to the administrator and the Securitization Financing Providers. The cost of an advance backstopping a letter of credit issued under the Securitization Facility is determined by two factors: (a) a program fee of 2.65% per year and payable on each settlement date to each Securitization Financing Provider deemed to have made such an advance and (b) the “discount,” which is calculated based on each Securitization Financing Provider’s costs, including its cost of the issuance and placement of short term promissory notes to fund such an advance. On May 9, 2016, the Securitization Facility was amended to exclude account receivables in respect of certain disposed mining operations of one of the Debtors and to effect the release of certain liens relating to such account receivables. Going Concern As a result of extremely challenging current market conditions, the Company believes it will require a significant restructuring of its balance sheet in order to continue as a going concern in the long term. The Company’s ability to continue as a going concern is dependent upon, among other things, improvement in current market conditions, its ability to become profitable and maintain profitability and its ability to successfully implement its Chapter 11 plan strategy. As a result of the Bankruptcy Petitions, the realization of the Debtors’ assets and the satisfaction of liabilities are subject to significant uncertainty. While operating as a debtor-in-possession pursuant to the Bankruptcy Code, the Company may sell or otherwise dispose of or liquidate assets or settle liabilities, subject to the approval of the Court or as otherwise permitted in the ordinary course of business for amounts other than those reflected in the accompanying consolidated financial statements. Further, the Chapter 11 plan is likely to materially change the amounts and classifications of assets and liabilities reported in the Company’s Condensed Consolidated Financial Statements. The accompanying Condensed Consolidated Financial Statements have been prepared assuming that the Company will continue as a going concern. The accompanying consolidated financial statements do not include any adjustments related to the recoverability and classification of assets or the amounts and classification of liabilities that might be necessary should the Company be unable to continue as a going concern.

Accounting Policies

Accounting Policies	6 Months Ended
	Jun. 30, 2016
Accounting Policies [Abstract]
Accounting Policies	Accounting Policies In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update No. 2015-03 (“ASU 2015-03”), Simplifying the Presentation of Debt Issuance Costs. ASU 2015-03 requires debt issuance costs related to a recognized debt liability to be presented in the balance sheet as a direct deduction from the carrying amount of that liability, consistent with debt discounts. The Company adopted ASU 2015-03 in the first quarter of 2016 as mandated by the standard. Previously reported "other current assets" and "current maturities of debt" have been revised to reflect the retrospective application of the standard. The following reflects the retrospective application: December 31, 2015 (in thousands) Other current assets, prior to revision $ 104,723 Revision of debt issuance costs (64,857 ) Other current assets, as revised $ 39,866 Current maturities of debt, prior to revision $ 5,107,210 Revision of debt issuance costs (64,857 ) Current maturities of debt, as revised $ 5,042,353

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	6 Months Ended
	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income The following items are included in accumulated other comprehensive income ("AOCI"): Pension, Postretirement and Other Accumulated Post- Other Derivative Employment Available-for- Comprehensive Instruments Benefits Sale Securities Income (In thousands) Balance at December 31, 2015 $ 325 $ (721 ) $ (1,419 ) $ (1,815 ) Unrealized gains (losses) (65 ) — 507 442 Amounts reclassified from AOCI (240 ) (3,606 ) 1,857 (1,989 ) Balance at June 30, 2016 $ 20 $ (4,327 ) $ 945 $ (3,362 ) The following amounts were reclassified out of AOCI: Amounts Reclassified from AOCI Line Item in the Condensed Consolidated Statement of Operations Three Months Ended June 30, Six Months Ended June 30, Details About AOCI Components 2016 2015 2016 2015 (In thousands) Derivative instruments $ 96 $ 2,727 $ 321 $ 3,208 Revenues — (983 ) (81 ) (1,157 ) Benefit from income taxes $ 96 $ 1,744 $ 240 $ 2,051 Net of tax Pension, postretirement and other post-employment benefits Amortization of prior service credits (1) $ 2,672 $ 2,083 $ 5,344 $ 4,167 Amortization of actuarial gains (losses), net (1) 77 (5,556 ) (1,257 ) (7,934 ) 2,749 (3,473 ) 4,087 (3,767 ) — 1,251 (481 ) 1,356 Benefit from income taxes $ 2,749 $ (2,222 ) $ 3,606 $ (2,411 ) Net of tax Available-for-sale securities $ — $ (1,430 ) $ (2,895 ) $ (4,227 ) Interest and investment income — 549 1,038 1,556 Benefit from income taxes $ — $ (881 ) $ (1,857 ) $ (2,671 ) Net of tax 1 Production-related benefits and workers' compensation costs are included in inventoriable production costs.

Reorganization items, net

Reorganization items, net	6 Months Ended
	Jun. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Reorganization items, net	Reorganization items, net In accordance with Accounting Codification Standard 852, "Reorganizations," the statement of operations shall portray the results of operations of the reporting entity while it is in Chapter 11. Revenues, expenses (including professional fees), realized gains and losses, and provisions for losses resulting from reorganization and restructuring of the business shall be reported separately as reorganization items. During the three months ended June 30, 2016 , the Company recorded a charge of $21.3 million in "Reorganization items, net" comprised of professional fee expense of $22.3 million , partially offset by non-cash gains on rejected contracts of $1.0 million . Net cash paid for "Reorganization items, net" totaled $13.6 million during the three months ended June 30, 2016 . During the six months ended June 30, 2016 , the Company recorded a charge of $25.1 million in "Reorganization items, net" comprised of professional fee expense of $40.0 million , partially offset by non-cash gains on rejected contracts of $14.9 million . Net cash paid for "Reorganization items, net" totaled $15.1 million during the six months ended June 30, 2016 .

Liabilities Subject to Compromi

Liabilities Subject to Compromise	6 Months Ended
	Jun. 30, 2016
Reorganizations [Abstract]
Liabilities Subject to Compromise	Liabilities Subject to Compromise Liabilities subject to compromise include unsecured or under-secured liabilities incurred prior to the Chapter 11 filing. These liabilities represent the amounts expected to be allowed on known or potential claims to be resolved through the Chapter 11 proceedings and remain subject to future adjustments based on negotiated settlements with claimants, actions of the Court, rejection of executory contracts, proofs of claims or other events. Additionally, liabilities subject to compromise also include certain items that may be assumed under a plan of reorganization, and as such, may be subsequently reclassified to liabilities not subject to compromise. Generally, actions to enforce or otherwise effect payment of pre-petition liabilities are stayed. Liabilities subject to compromise consists of the following: June 30, 2016 (in thousands) Previously Reported Balance Sheet Line Debt $ 5,063,095 Accrued expenses and current liabilities 205,568 Accounts payable 100,047 Noncurrent liabilities 56,114 Accrued pension benefits 5,632 Total Liabilities Subject to Compromise $ 5,430,456 The debt balance included above is net of debt issuance costs of $64.9 million ; for additional information on debt, see Note 11, "Debt and Financing Arrangements."

Asset Impairments and Mine Clos

Asset Impairments and Mine Closure Costs	6 Months Ended
	Jun. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Asset Impairment and Mine Closure Costs	Asset Impairment and Mine Closure Costs During the second quarter of 2016 , the Company recorded $43.7 million of "Asset impairment and mine closure costs" in the Condensed Consolidated Statements of Operations. The amount includes the following: a $38.0 million impairment of the Company's equity investment in a brownfield bulk commodity terminal on the Columbia River in Longview, Washington as the Company relinquished its ownership rights in exchange for future throughput rights; a $3.6 million curtailment charge related to the Company's pension, postretirement health and black lung actuarial liabilities due to headcount reductions in the first half of the year; and $2.1 million of severance expense related to headcount reductions during the quarter. During the first quarter of 2016, the Company recorded $85.5 million of "Asset impairment and mine closure costs" in the Condensed Consolidated Statements of Operations. The amount included the following: a $74.1 million impairment of coal reserves and surface land in Kentucky that are being leased to a mining company that announced plans to idle its current mining operations related to those reserves during the quarter; $5.1 million of severance expense related to headcount reductions at Company operations; $3.4 million related to an impairment charge on the portion of an advance royalty balance on a reserve base mined at the Company's Mountain Laurel operation that will not be recouped; and $2.9 million related to an other-than-temporary-impairment charge on an available-for-sale security. During the second quarter of 2015 , the Company recorded $19.1 million of "Asset impairment and mine closure costs" in the Condensed Consolidated Statements of Operations. An impairment charge of $12.2 million relates to the portion of an advance royalty balance on a reserve base mined at the Company's Mountain Laurel, Spruce and Briar Branch operations that will not be recouped based on latest estimates of sales volumes and pricing through the recoupment period which runs through March 2017. Additionally, the Company recorded a $5.6 million impairment charge related to the closure of a higher cost mining complex, Cumberland River, serving the metallurgical coal markets.

Inventories

Inventories	6 Months Ended
	Jun. 30, 2016
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consist of the following: June 30, December 31, 2016 2015 (In thousands) Coal $ 61,874 $ 85,043 Repair parts and supplies 110,824 111,677 $ 172,698 $ 196,720 The repair parts and supplies are stated net of an allowance for slow-moving and obsolete inventories of $6.5 million at June 30, 2016 and $6.0 million at December 31, 2015 .

Investments in Available-for-Sa

Investments in Available-for-Sale Securities	6 Months Ended
	Jun. 30, 2016
Available-for-sale Securities [Abstract]
Investments in Available-for-Sale Securities	Investments in Available-for-Sale Securities The Company has invested in marketable debt securities, primarily highly liquid investment grade corporate bonds. These investments are held in the custody of a major financial institution. These securities, along with the Company's investments in marketable equity securities, are classified as available-for-sale securities and, accordingly, the unrealized gains and losses are recorded through other comprehensive income. The Company's investments in available-for-sale marketable securities are as follows: June 30, 2016 Balance Sheet Classification Gross Unrealized Fair Short-Term Other Cost Basis Gains Losses Value Investments Assets (In thousands) Available-for-sale: U.S. government and agency securities $ 47,392 $ 120 $ — $ 47,512 $ 47,512 $ — Corporate notes and bonds 155,952 38 (85 ) 155,905 155,905 — Equity securities 1,165 1,064 — 2,229 — 2,229 Total Investments $ 204,509 $ 1,222 $ (85 ) $ 205,646 $ 203,417 $ 2,229 December 31, 2015 Balance Sheet Classification Gross Unrealized Fair Short-Term Other Cost Basis Gains Losses Value Investments Assets (In thousands) Available-for-sale: U.S. government and agency securities $ 10,007 $ — $ (12 ) $ 9,995 $ 9,995 $ — Corporate notes and bonds 190,496 — (299 ) 190,197 190,197 — Equity securities 3,938 668 (2,888 ) 1,718 — 1,718 Total Investments $ 204,441 $ 668 $ (3,199 ) $ 201,910 $ 200,192 $ 1,718 The aggregate fair value of investments with unrealized losses that were owned for less than a year was $73.5 million and $184.6 million at June 30, 2016 and December 31, 2015 , respectively. The aggregate fair value of investments with unrealized losses that were owned for over a year, and were also in a continuous unrealized loss position during that time, was $35.7 million and $15.8 million at June 30, 2016 and December 31, 2015 , respectively. The unrealized losses in the Company's portfolio at June 30, 2016 are the result of normal market fluctuations. The Company does not currently intend to sell these investments before recovery of their amortized cost base. The debt securities outstanding at June 30, 2016 have maturity dates ranging from the third quarter of 2016 through the fourth quarter of 2017 . The Company classifies its investments as current based on the nature of the investments and their availability to provide cash for use in current operations.

Derivatives

Derivatives	6 Months Ended
	Jun. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Derivatives Diesel fuel price risk management The Company is exposed to price risk with respect to diesel fuel purchased for use in its operations. The Company anticipates purchasing approximately 41 to 46 million gallons of diesel fuel for use in its operations during 2016 . To protect the Company’s cash flows from increases in the price of diesel fuel for its operations, the Company uses forward physical diesel purchase contracts and purchased heating oil call options. At June 30, 2016 , the Company had protected the price of approximately 62% of its expected purchases for the remainder of the year with out-of-the-money call options with an average strike price of $2.25 per gallon. Due to the drop in heating oil prices, the Company has layered in 9.8 million gallons of at-the-money call options for the remainder of 2016 representing 49% of expected purchases at an average strike price of $1.32 per gallon. Additionally, the Company has protected approximately 18% of its expected 2017 purchases with out-of-the-money call options with an average strike price of $1.60 per gallon. At June 30, 2016 , the Company had outstanding heating oil call options for approximately 20 million gallons for the purpose of managing the price risk associated with future diesel purchases. These positions are not accounted for as hedges. Coal price risk management positions The Company may sell or purchase forward contracts, swaps and options in the over-the-counter coal market in order to manage its exposure to coal prices. The Company has exposure to the risk of fluctuating coal prices related to forecasted sales or purchases of coal or to the risk of changes in the fair value of a fixed price physical sales contract. Certain derivative contracts may be designated as hedges of these risks. At June 30, 2016 , the Company held derivatives for risk management purposes that are expected to settle in the following years: (Tons in thousands) 2016 2017 Total Coal sales 265 480 745 Coal purchases 165 — 165 The Company has also entered into a nominal quantity of natural gas put options to protect the Company from decreases in natural gas prices, which could impact thermal coal demand. These options are not accounted for as hedges. Additionally, the Company has also entered into a nominal quantity of foreign currency put options protecting for decreases in the Australian to United States dollar exchange rate, which could impact metallurgical coal demand. These options are not accounted for as hedges. Coal trading positions The Company may sell or purchase forward contracts, swaps and options in the over-the-counter coal market for trading purposes. The Company is exposed to the risk of changes in coal prices on the value of its coal trading portfolio. The estimated future realization of the value of the trading portfolio is $2.7 million of gains during the remainder of 2016 . Tabular derivatives disclosures The Company has master netting agreements with all of its counterparties which allow for the settlement of contracts in an asset position with contracts in a liability position in the event of default or termination. Such netting arrangements reduce the Company’s credit exposure related to these counterparties. For classification purposes, the Company records the net fair value of all the positions with a given counterparty as a net asset or liability in the Condensed Consolidated Balance Sheets. The amounts shown in the table below represent the fair value position of individual contracts, and not the net position presented in the accompanying Condensed Consolidated Balance Sheets. The fair value and location of derivatives reflected in the accompanying Condensed Consolidated Balance Sheets are as follows: June 30, 2016 December 31, 2015 Fair Value of Derivatives Asset Liability Asset Liability (In thousands) Derivative Derivative Derivative Derivative Derivatives Designated as Hedging Instruments Coal $ 4 $ (50 ) $ 4 $ (20 ) Derivatives Not Designated as Hedging Instruments Heating oil -- diesel purchases 4,266 — 1,017 — Coal -- held for trading purposes 46,401 (43,798 ) 110,653 (104,814 ) Coal -- risk management 1,306 (438 ) 3,912 (1,947 ) Natural gas 190 — 494 (247 ) Foreign currency 323 — — — Total 52,486 (44,236 ) 116,076 (107,008 ) Total derivatives 52,490 (44,286 ) 116,080 (107,028 ) Effect of counterparty netting (43,810 ) 43,810 (107,028 ) 107,028 Net derivatives as classified in the balance sheets $ 8,680 $ (476 ) $ 8,204 $ 9,052 $ — $ 9,052 June 30, 2016 December 31, 2015 Net derivatives as reflected on the balance sheets (in thousands) Heating oil and foreign currency Other current assets $ 4,589 $ 1,017 Coal and natural gas Coal derivative assets 4,091 8,035 Accrued expenses and other current liabilities (476 ) — $ 8,204 $ 9,052 The Company had a current asset for the right to reclaim cash collateral of $0.3 million at June 30, 2016 and the right to reclaim cash collateral of $1.7 million at December 31, 2015 , respectively. These amounts are not included with the derivatives presented in the table above and are included in "other current assets" in the accompanying Condensed Consolidated Balance Sheets. The effects of derivatives on measures of financial performance are as follows: Derivatives used in Cash Flow Hedging Relationships (in thousands) Three Months Ended June 30, Gain (Loss) Recognized in Other Comprehensive Income(Effective Portion) Gains (Losses) Reclassified from Other Comprehensive Income into Income (Effective Portion) 2016 2015 2016 2015 Coal sales (1) $ (73 ) $ (1,163 ) $ 157 $ 4,990 Coal purchases (2) 6 687 (61 ) (2,263 ) Totals $ (67 ) $ (476 ) $ 96 $ 2,727 No ineffectiveness or amounts excluded from effectiveness testing relating to the Company’s cash flow hedging relationships were recognized in the results of operations in the three month periods ended June 30, 2016 and 2015 . Derivatives Not Designated as Hedging Instruments (in thousands) Three Months Ended June 30, Gain (Loss) Recognized 2016 2015 Coal — unrealized (3) $ 19 $ (875 ) Coal — realized (4) $ (180 ) $ 826 Natural gas — unrealized (3) $ 235 $ (221 ) Heating oil — diesel purchases (4) $ 2,039 $ 628 Foreign currency (4) $ 34 $ — ____________________________________________________________ Location in statement of operations: (1) — Revenues (2) — Cost of sales (3) — Change in fair value of coal derivatives and coal trading activities, net (4) — Other operating (income) expense, net Derivatives used in Cash Flow Hedging Relationships (in thousands) Six Months Ended June 30, Gain (Loss) Recognized in Other Comprehensive Income(Effective Portion) Gains (Losses) Reclassified from Other Comprehensive Income into Income 2016 2015 2016 2015 Coal sales (1) $ (60 ) $ 9,102 $ 1,526 $ 5,872 Coal purchases (2) (5 ) (4,051 ) (1,205 ) (2,664 ) Totals $ (65 ) $ 5,051 $ 321 $ 3,208 No ineffectiveness or amounts excluded from effectiveness testing relating to the Company’s cash flow hedging relationships were recognized in the results of operations in the six month periods ended June 30, 2016 and 2015 . Derivatives Not Designated as Hedging Instruments (in thousands) Six Months Ended June 30, Gain (Loss) Recognized 2016 2015 Coal — unrealized (3) $ (1,096 ) $ (1,286 ) Coal — realized (4) $ (343 ) $ 1,917 Natural gas — unrealized (3) $ (384 ) $ (62 ) Heating oil — diesel purchases (4) $ 1,596 $ (1,737 ) Foreign currency (4) $ (137 ) $ — ____________________________________________________________ Location in statement of operations: (1) — Revenues (2) — Cost of sales (3) — Change in fair value of coal derivatives and coal trading activities, net (4) — Other operating (income) expense, net Based on fair values at June 30, 2016 , amounts on derivative contracts designated as hedge instruments in cash flow hedges to be reclassified from other comprehensive income into earnings during the next twelve months are immaterial. Related to its trading portfolio, the Company recognized net unrealized and realized losses of $1.0 million and net unrealized and realized losses of $0.1 million during the three months ended June 30, 2016 and 2015 , respectively; and net unrealized and realized losses of $1.0 million and net unrealized and realized losses of $1.1 million during the six months ended June 30, 2016 and 2015 . Gains and losses from trading activities are included in the caption “Change in fair value of coal derivatives and coal trading activities, net” in the accompanying Condensed Consolidated Statements of Operations, and are not included in the previous tables reflecting the effects of derivatives on measures of financial performance.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	6 Months Ended
	Jun. 30, 2016
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consist of the following: June 30, December 31, 2016 2015 (In thousands) Payroll and employee benefits $ 58,801 $ 58,423 Taxes other than income taxes 97,445 104,755 Interest 162,506 119,785 Acquired sales contracts — 3,852 Workers’ compensation 13,576 16,875 Asset retirement obligations 17,297 13,795 Other 8,971 11,965 $ 358,596 $ 329,450 Less: liabilities subject to compromise (205,568 ) — $ 153,028 $ 329,450

Debt and Financing Arrangements

Debt and Financing Arrangements	6 Months Ended
	Jun. 30, 2016
Debt Disclosure [Abstract]
Debt and Financing Arrangements	Debt and Financing Arrangements June 30, December 31, 2016 2015 (In thousands) Term loan due 2018 ($1.9 billion face value) $ 1,875,429 $ 1,875,429 7.00% senior notes due 2019 at par 1,000,000 1,000,000 9.875% senior notes due 2019 ($375.0 million face value) 365,600 365,600 8.00% senior secured notes due 2019 at par 350,000 350,000 7.25% senior notes due 2020 at par 500,000 500,000 7.25% senior notes due 2021 at par 1,000,000 1,000,000 Other 36,923 47,134 Debt issuance costs (64,857 ) (64,857 ) 5,063,095 5,073,306 Less: liabilities subject to compromise 5,063,095 — Less: current maturities of debt — 5,042,353 Long-term debt $ — $ 30,953 Acceleration of Debt Obligations; Automatic Stay The filing of the Bankruptcy Petitions constituted an event of default that accelerated the Company's obligations under the documents governing each of its 7.00% senior notes due 2019, 9.875% senior notes due 2019, 8.00% senior secured second lien notes due 2019, 7.25% senior notes due 2020, 7.25% senior notes due 2021 (together, the “senior notes”) and senior secured first lien term loan due 2018. Immediately after filing the Bankruptcy Petitions, the Company began notifying all known current or potential creditors of the Debtors of the bankruptcy filings. Pursuant to Section 362 of the Bankruptcy Code, the filing of the Bankruptcy Petitions automatically stayed most actions against the Debtors, including actions to collect indebtedness incurred prior to the Petition Date or to exercise control over the Debtors’ property. Subject to certain exceptions under the Bankruptcy Code, the filing of the Debtors’ Chapter 11 Cases also automatically stayed the continuation of most legal proceedings or the filing of other actions against or on behalf of the Debtors or their property to recover on, collect or secure a claim arising prior to the Petition Date or to exercise control over property of the Debtors’ bankruptcy estates, unless and until the Court modifies or lifts the automatic stay as to any such claim. Notwithstanding the general application of the automatic stay described above, governmental authorities may determine to continue actions brought under their police and regulatory powers. Securitization Agreement On January 13, 2016, the Company agreed with its securitization financing providers (the “Securitization Financing Providers”) that, subject to certain amendments (the “Amendments”), they will continue the $200 million trade accounts receivable securitization facility provided to Arch Receivable Company, LLC, a non-debtor special-purpose entity that is a wholly owned subsidiary of the Company (“Arch Receivable”) (the “Securitization Facility”). Pursuant to the Amendments, which have been approved by the Court on a final basis, the Debtors agreed to a revised schedule of fees payable to the administrator and the Securitization Financing Providers. The cost of an advance backstopping a letter of credit issued under the Securitization Facility is determined by two factors: (a) a program fee of 2.65% per year and payable on each settlement date to each Securitization Financing Provider deemed to have made such an advance and (b) the “discount,” which is calculated based on each Securitization Financing Provider’s costs, including its cost of the issuance and placement of short term promissory notes to fund such an advance. In connection with the Securitization Facility, Arch Receivable has granted to the administrator (for the benefit of the securitization purchasers) a first priority security interest in all of its assets, including all outstanding accounts receivable generated by the Debtors from the sale of coal and sold through the Securitization Facility (including collections, proceeds and certain other interests related thereto) (the “Receivables”) and all proceeds thereof. The agreements governing the Securitization Facility provide for the grant of analogous security interests by certain Debtors that generate Receivables from the sale of coal (such Debtors, the “Originators”). The agreements expressly state that the transfers of Receivables from the Originators to Arch and from Arch to Arch Receivable are intended to be true sales of the Receivables. However, if, against the intent of the parties (and notwithstanding entry of an order by the Court which provides that the transfers of the Receivables constitute true sales), any such transfer is recharacterized as a loan or extension of credit, each Originator has granted a first priority prepetition security interest in the Receivables and certain related collateral, pursuant to the agreements governing the Securitization Facility, for the ultimate benefit of the administrator and the Securitization Financing Providers (the “Liens”). The Debtors have agreed, in connection with the Amendments, to effectively extend such Liens to cover Receivables generated on or after the Petition Date. The Originators do not guarantee the collection of Receivables that have been transferred to Arch Receivable. However, the Originators are obligated to reimburse Arch Receivable for inaccuracy of certain representations and warranties, dilution items with respect to Receivables and certain other limited indemnities (such obligations, the “Repayment Amounts”). Under the agreements governing the Securitization Facility, Arch Receivable is entitled to apply Repayment Amounts to amounts owed under the Securitization Facility. Further, the Company has executed a performance guarantee through which it has promised to fulfill, or cause Arch Receivable, the designated servicer and each Originator to fulfill, each of their obligations under the agreements governing the Securitization Facility. In addition, as contemplated by the Amendments, the Originators have also executed a performance guarantee promising to fulfill obligations of all Originators under the agreements. In addition, in connection with the Amendments, the Debtors have granted superpriority claims against the Debtors and in favor of Arch Receivable, the administrator and the Securitization Financing Providers in respect of certain of the Debtors’ obligations under the agreements governing the Securitization Facility, including the Repayment Amounts and certain other limited indemnification and other obligations of the Debtors under the agreements. On May 9, 2016, the Securitization Facility was amended to exclude account receivables in respect of certain disposed mining operations of one of the Debtors and to effect the release of certain liens relating to such account receivables. Debtor-In-Possession Financing On January 21, 2016, the Superpriority Secured Debtor-in-Possession Credit Agreement (as amended on March 4, 2016, March 28, 2016, April 26, 2016, June 10, 2016 and June 23, 2016, the “DIP Credit Agreement”) was entered into by and among the Company, as borrower, certain of the Debtors, as guarantors (the “Guarantors” and, together with the Company, the “Loan Parties”), the lenders from time to time party thereto (the “DIP Lenders”) and Wilmington Trust, National Association, as administrative agent and collateral agent for the DIP Lenders (in such capacities, the “DIP Agent”). The DIP Credit Agreement, which has been approved by the Court on a final basis, provides for a super-priority senior secured debtor-in-possession credit facility (the “DIP Facility”) consisting of term loans (collectively, the “DIP Term Loan”) in the aggregate principal amount of up to $275 million . The maturity date of the DIP Facility is the earliest of (i) January 31, 2017, (ii) the date of the substantial consummation of a plan of reorganization that is confirmed pursuant to an order of the Court, (iii) the consummation of the sale of all or substantially all of the assets of the Loan Parties pursuant to Section 363 of the Bankruptcy Code and (iv) the date the obligations under the DIP Facility are accelerated pursuant to the terms of the DIP Credit Agreement. Borrowings under the DIP Facility bear interest at an interest rate per annum equal to, at the Company’s option (i) LIBOR plus 9.00% , subject to a 1.00% LIBOR floor or (ii) the base rate plus 8.00% . Obligations under the DIP Credit Agreement are guaranteed on a super-priority senior secured basis by all existing and future wholly-owned domestic subsidiaries of Arch, and all newly created or acquired wholly-owned domestic subsidiaries of Arch, subject to customary limited exceptions. The lenders under the DIP Credit Agreement have a first priority lien on all encumbered and unencumbered assets of the Loan Parties (the “DIP Lien”), subject to a $75 million carve-out for super-priority claims relating to the Debtors’ self-bonding obligations in Wyoming, a customary professional fees carve-out and certain exceptions. The Loan Parties are subject to certain financial maintenance covenants under the DIP Credit Agreement, including, without limitation, (i) maximum capital expenditures and (ii) minimum liquidity (defined as unrestricted cash and cash equivalents of the Company and its domestic subsidiaries (other than any securitization subsidiary or bonding subsidiary), plus withdrawable funds from brokerage accounts of the Company and its domestic subsidiaries (other than any securitization subsidiary or bonding subsidiary) plus any unused commitments that are available to be drawn by the Company pursuant to the terms of the DIP Credit Agreement) of (A) $300 million prior to the entry of the Final Order (as defined below) and (B) $500 million following the entry of the Final Order, in each case tested on a monthly basis. The DIP Credit Agreement contains customary affirmative and negative covenants and representations for debtor-in-possession financings. In addition to customary events of default for debtor-in-possession financings, the DIP Credit Agreement contains milestones relating to the Chapter 11 Cases and any failure to comply with such milestones constitutes an event of default. The DIP Facility is subject to certain usual and customary prepayment events, including 100% of net cash proceeds of (i) debt issuances (other than debt permitted to be incurred under the terms of the DIP Credit Agreement), (ii) non-ordinary course asset sales or dispositions in excess of $50 million in the aggregate (with no individual asset sale or disposition in excess of $7.5 million ) and (iii) any casualty event in excess of $50 million in the aggregate, subject to customary reinvestment rights, in each case to be applied to prepay the DIP Term Loan. At a hearing held on February 23, 2016 in the Chapter 11 Cases, the Court issued an order approving the DIP Facility on a final basis (the "Final Order"), overruling the objections of the Creditors' Committee and certain other parties who asserted, among other things, that the DIP Facility was unnecessary and argued that the Debtors should enter into an alternate debtor-in-possession financing facility proposed by certain members of the Creditors' Committee. The Company entered into an amendment to the DIP Credit Agreement, dated as of April 26, 2016, which extended the deadline for the filing of a plan of reorganization and accompanying disclosure statement from April 26, 2016 to May 5, 2016. The Company entered into an amendment to the DIP Credit Agreement, dated as of July 20, 2016. See Note 18, "Subsequent Events." The Company paid $15.6 million in financing fees related to the DIP Facility which have been deferred and are being amortized over the term of the DIP Facility. Contractual Interest Expense The Company has recorded interest expense of $45.3 million and $89.7 million for the three and six months ended June 30, 2016 compared to $99.6 million and $198.8 million for the three and six months ended June 30, 2015 . The reduction in interest expense in the current year is due to the Company's bankruptcy filing. The contractual interest expense parenthetically disclosed on the face of the income statement represents interest expense that the Company was obligated to pay prior to the bankruptcy filing.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes During 2016, the Company determined it was more likely than not that the federal and state net operating losses it expects to generate in 2016 will not be realized based on projections of future taxable income. Accordingly, the estimated annual effective rate for the year ended December 31, 2016 includes the impact of recording a valuation allowance against these attributes. During the six months ended June 30, 2016 , the Company realized a net tax benefit of $1.4 million , which included a valuation allowance of $151.0 million for federal net operating losses and tax credits and $7.0 million for the state net operating losses. During the six months ended June 30, 2015 , the Company increased its valuation allowance for the portion of the federal and state net operating losses it expected to generate in 2015. The Company increased its valuation allowance by $104.6 million for the federal net operating losses and $5.8 million for the state net operating losses.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The hierarchy of fair value measurements assigns a level to fair value measurements based on the inputs used in the respective valuation techniques. The levels of the hierarchy, as defined below, give the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. · Level 1 is defined as observable inputs such as quoted prices in active markets for identical assets. Level 1 assets include available-for-sale equity securities, U.S. Treasury securities, and coal futures that are submitted for clearing on the New York Mercantile Exchange. · Level 2 is defined as observable inputs other than Level 1 prices. These include quoted prices for similar assets or liabilities in an active market, quoted prices for identical assets and liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. The Company’s level 2 assets and liabilities include U.S. government agency securities and commodity contracts (coal and heating oil) with fair values derived from quoted prices in over-the-counter markets or from prices received from direct broker quotes. · Level 3 is defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. These include the Company’s commodity option contracts (coal, natural gas and heating oil) valued using modeling techniques, such as Black-Scholes, that require the use of inputs, particularly volatility, that are rarely observable. Changes in the unobservable inputs would not have a significant impact on the reported Level 3 fair values at June 30, 2016 . The table below sets forth, by level, the Company’s financial assets and liabilities that are recorded at fair value in the accompanying condensed consolidated balance sheet: June 30, 2016 Total Level 1 Level 2 Level 3 (In thousands) Assets: Investments in marketable securities $ 205,646 $ 49,742 $ 155,904 $ — Derivatives 8,680 2,893 977 4,810 Total assets $ 214,326 $ 52,635 $ 156,881 $ 4,810 Liabilities: Derivatives $ 476 $ 437 $ — $ 39 The Company’s contracts with its counterparties allow for the settlement of contracts in an asset position with contracts in a liability position in the event of default or termination. For classification purposes, the Company records the net fair value of all the positions with these counterparties as a net asset or liability. Each level in the table above displays the underlying contracts according to their classification in the accompanying Condensed Consolidated Balance Sheet, based on this counterparty netting. The following table summarizes the change in the fair values of financial instruments categorized as Level 3. Three Months Ended June 30, 2016 Six Months Ended June 30, 2016 (In thousands) Balance, beginning of period $ 2,702 $ 2,432 Realized and unrealized gains recognized in earnings, net 1,061 202 Realized and unrealized gains recognized in other comprehensive income, net — — Purchases 2,073 3,435 Issuances (255 ) (488 ) Settlements (810 ) (810 ) Ending balance $ 4,771 $ 4,771 Net unrealized gains of $1.4 million and $1.0 million were recognized in the Condensed Consolidated Statement of Operations during the three and six months ended June 30, 2016 related to Level 3 financial instruments held on June 30, 2016 . Fair Value of Long-Term Debt At June 30, 2016 and December 31, 2015 , the fair value of the Company’s debt, including amounts classified as current, was $928.5 million and $937.1 million , respectively. Fair values are based upon observed prices in an active market, when available, or from valuation models using market information, which fall into Level 2 in the fair value hierarchy.

Loss Per Common Share

Loss Per Common Share	6 Months Ended
	Jun. 30, 2016
Earnings Per Share [Abstract]
Loss Per Common Share	Loss Per Common Share The effect of options, restricted stock and restricted stock units that were excluded from the calculation of diluted weighted average shares outstanding because the exercise price or grant price of the securities exceeded the average market price of the Company's common stock was immaterial for both the three and six months ended June 30, 2016 , and 2015, respectively. The weighted average share impact of options, restricted stock and restricted stock units that were excluded from the calculation of weighted average shares due to the Company's incurring a net loss was immaterial for both the three and six months ended June 30, 2016 and 2015, respectively.

Employee Benefit Plans

Employee Benefit Plans	6 Months Ended
	Jun. 30, 2016
Pension and Other Postretirement Benefit Expense [Abstract]
Employee Benefit Plans	Employee Benefit Plans The following table details the components of pension benefit costs (credits): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 (In thousands) Service cost $ — $ 1 $ — $ 5 Interest cost 3,197 3,695 6,535 7,265 Expected return on plan assets (4,444 ) (4,466 ) (8,982 ) (10,231 ) Curtailments 454 — 454 — Amortization of other actuarial losses 924 3,185 1,681 5,243 Net costs (credits) $ 131 $ 2,415 $ (312 ) $ 2,282 The following table details the components of other postretirement benefit costs (credits): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 (In thousands) Service cost $ 105 $ 200 $ 265 $ 433 Interest cost 1,138 308 2,272 643 Curtailments (970 ) — (970 ) — Amortization of prior service credits (2,672 ) (2,083 ) (5,345 ) (4,167 ) Amortization of other actuarial losses (gains) (566 ) (599 ) (1,132 ) (1,055 ) Net credit $ (2,965 ) $ (2,174 ) $ (4,910 ) $ (4,146 )

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company accrues for costs related to contingencies when a loss is probable and the amount is reasonably determinable. Disclosure of contingencies is included in the financial statements when it is at least reasonably possible that a material loss or an additional material loss in excess of amounts already accrued may be incurred. In addition, the Company is a party to numerous other claims and lawsuits with respect to various matters. As of June 30, 2016 and December 31, 2015 , the Company had accrued $2.8 million and $2.8 million , respectively, for all legal matters, of which all amounts are classified as current. The ultimate resolution of any such legal matter could result in outcomes which may be materially different from amounts the Company has accrued for such matters. Pursuant to Section 362 of the Bankruptcy Code, the filing of the Bankruptcy Petitions automatically stayed most actions against the Debtors, including actions to collect indebtedness incurred prior to the Petition Date or to exercise control over the Debtors' property. Subject to certain exceptions under the Bankruptcy Code, the filing of the Debtors' Chapter 11 Cases also automatically stayed the continuation of most legal proceedings or the filing of other actions against or on behalf of the Debtors or their property to recover on, collect or secure a claim arising prior to the Petition Date or to exercise control over property of the Debtors' bankruptcy estates, unless and until the Court modifies or lifts the automatic stay as to any such claim. Notwithstanding the general application of the automatic stay described above, governmental authorities may determine to continue actions brought under their police and regulatory powers.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2016
Segment Reporting [Abstract]
Segment Information	Segment Information The Company's reportable business segments are based on the major coal producing basins in which the Company operates and may include a number of mine complexes. The Company manages its coal sales by coal basin, not by individual mining complex. Geology, coal transportation routes to customers, regulatory environments and coal quality or type are characteristic to a basin, and, accordingly, market and contract pricing have developed by coal basin. Mining operations are evaluated based on adjusted EBITDA, as well as on other non-financial measures, such as safety and environmental performance. The Company’s reportable segments are the Powder River Basin (PRB) segment, with operations in Wyoming; and the Appalachia (APP) segment, with operations primarily in West Virginia. The “Other” category combines other operating segments and includes the Company’s coal mining operations in Colorado and Illinois. Operating segment results for the three and six months ended June 30, 2016 and 2015 are presented below. The Company uses Adjusted EBITDA to assess the operating segments’ performance and to allocate resources. The Company’s management believes that Adjusted EBITDA presents a useful measure of the Company's ability to service existing debt and incur additional debt based on ongoing operations. Corporate, Other and Eliminations includes the change in fair value of coal derivatives and coal trading activities, net; corporate overhead; land management; other support functions; and the elimination of intercompany transactions. PRB APP Other Operating Segments Corporate, Other and Eliminations Consolidated (in thousands) Three Months Ended June 30, 2016 Revenues $ 207,735 $ 170,940 $ 41,623 $ — $ 420,298 Adjusted EBITDA 15,932 (5,963 ) 595 (18,924 ) (8,360 ) Depreciation, depletion and amortization 30,145 19,422 8,110 782 58,459 Amortization of acquired sales contracts, net 76 (75 ) — — 1 Capital expenditures 489 6,740 949 60,033 68,211 Three Months Ended June 30, 2015 Revenues $ 342,480 $ 224,298 $ 77,684 $ — $ 644,462 Adjusted EBITDA 56,654 11,427 7,456 (30,209 ) 45,328 Depreciation, depletion and amortization 42,711 42,203 10,834 1,624 97,372 Amortization of acquired sales contracts, net (761 ) (883 ) — — (1,644 ) Capital expenditures 4,425 7,948 1,668 62,440 76,481 Six Months Ended June 30, 2016 Revenues $ 430,857 $ 344,558 $ 72,989 $ — $ 848,404 Adjusted EBITDA 22,942 1,645 (2,732 ) (40,241 ) (18,386 ) Depreciation, depletion and amortization 62,905 41,751 16,043 1,459 122,158 Amortization of acquired sales contracts, net 30 (862 ) — — (832 ) Capital expenditures 499 10,369 2,910 60,359 74,137 Six Months Ended June 30, 2015 Revenues $ 733,686 $ 447,737 $ 140,044 $ — $ 1,321,467 Adjusted EBITDA 128,716 51,234 9,147 (61,997 ) 127,100 Depreciation, depletion and amortization 87,072 90,930 20,889 3,355 202,246 Amortization of acquired sales contracts, net (2,046 ) (2,988 ) — — (5,034 ) Capital expenditures 21,394 11,333 4,310 62,324 99,361 A reconciliation of adjusted EBITDA to consolidated loss before income taxes follows: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 (In thousands) Adjusted EBITDA $ (8,360 ) $ 45,328 $ (18,386 ) $ 127,100 Depreciation, depletion and amortization (58,459 ) (97,372 ) (122,158 ) (202,246 ) Amortization of acquired sales contracts, net (1 ) 1,644 832 5,034 Asset impairment and mine closure costs (43,701 ) (19,146 ) (129,221 ) (19,146 ) Interest expense, net (44,340 ) (98,612 ) (87,653 ) (195,491 ) Nonoperating expenses (21,271 ) (4,016 ) (27,359 ) (4,016 ) Loss before income taxes $ (176,132 ) $ (172,174 ) $ (383,945 ) $ (288,765 )

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2016
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Bankruptcy Items Approval of the Disclosure Statement; Solicitation of Votes on the Plan; Confirmation Hearing On July 6, 2016, the Company filed its Third Amended Joint Plan of Reorganization Under Chapter 11 of the Bankruptcy Code (the “Third Amended Plan”) and its Disclosure Statement for the Third Amended Plan. On July 8, 2016, the Court entered an order authorizing the Company to solicit acceptances to the Third Amended Plan, setting a voting deadline of August 31, 2016 and scheduling a Confirmation Hearing with respect to the Third Amended Plan on September 13, 2016. Restructuring Support Agreement As previously disclosed, on January 11, 2016 (the “Petition Date”), Arch Coal, Inc. (“Arch” or the “Company”) and substantially all of Arch’s wholly owned domestic subsidiaries (the “Filing Subsidiaries” and, together with Arch, the “Debtors”) filed voluntary petitions for reorganization under Chapter 11 of Title 11 of the U.S. Code in the United States Bankruptcy Court for the Eastern District of Missouri (the “Court”). As also previously disclosed, prior to the Petition Date, certain of the Debtors entered into a Restructuring Support Agreement, dated as of January 10, 2016, which agreement was amended (on February 25, 2016, March 28, 2016, April 26, 2016, May 5, 2016, June 10, 2016 and June 23, 2016). On July 5, 2016, the Debtors entered into an Amended and Restated Restructuring Support Agreement (the “Amended and Restated RSA”) with lenders holding more than 75% of the aggregate principal amount of loans outstanding under Arch’s pre-petition first lien credit facility, the statutory committee of unsecured creditors appointed in the Chapter 11 Cases pursuant to Section 1102 of the Bankruptcy Code (the “Committee”) and certain members of the Committee. Pursuant to the Amended and Restated RSA, the parties thereto have agreed, subject to certain terms and conditions to support, to vote for (as applicable) and not object to a plan of reorganization of the Debtors (the “Plan”) that includes the following terms: A. Holders of unsecured note claims (including second lien note claims) (the “Class of Unsecured Note Claims”) will receive their pro rata share of: i) shares of common stock of reorganized Arch Coal (“New Common Stock”) in an amount equal to 6% of the common stock of Arch Coal issued and outstanding upon consummation of the Plan, subject to dilution as set forth in the Plan; ii) at each holder’s election, (A) warrants, exercisable, at any time for a period of seven years from the effective date of the Plan, into shares of New Common Stock in an amount equal to 12% of the common stock of reorganized Arch Coal issued and outstanding upon consummation of the Plan (at a strike price based on total equity value of $1.425 billion ), on the terms and conditions set forth in the Plan, including anti-dilution and other adjustments to exercise price and number of shares, repurchases of shares of New Common Stock, issuance of capital stock below fair market value, mergers, recapitalizations, business combinations or other “organic changes” and whether such warrants will be exercisable for cash or on a cashless basis or (B) their pro rata share of an amount of cash equal to $25 million multiplied by the percentage of holders who receive cash in lieu of warrants; and iii) $22.636 million cash. Holders of all other general unsecured claims will receive their pro rata share of $7.364 million cash. B. An increase in the amount of cash distributions to the holders of claims under Arch’s pre-petition first lien credit facility (the “Senior Lenders”) from approximately $115 million to approximately $145 million . The percentage of New Common Stock distributed to Senior Lenders pursuant to the Plan will be reduced by the 6% of New Common Stock distributed to holders of general unsecured claims, and subject to further dilution as set forth in the Plan. C. GSO Capital will release any and all claims or causes of action against the Debtors and the Senior Lenders, including, without limitation, the claims asserted by GSO Capital in the complaint (the “Complaint”) filed on May 27, 2016 in Adversary Proceeding No. 16-04072, related to the Debtors, the Chapter 11 Cases and certain private debt exchange offers launched by certain of the Debtors on July 2, 2015 and the Complaint will be withdrawn with prejudice. In consideration for the settlement, GSO Capital will receive $5 million . D. Releases by the Company of all claims or causes of action under chapter 5 of the Bankruptcy Code against pre-petition trade creditors and the directors, officers and other employees Arch Coal, and all agents and representatives of the foregoing, and all claims or causes of action against the Senior Lenders. E. The standing motions [ECF Nos. [964] and [963]] will each be stayed, and the Debtors’, the Senior Lenders’ and all other parties in interest’s deadlines to object to or otherwise respond to the Standing Motions will be extended until the earlier of (A) the effective date of the Plan, upon which date the Standing Motions will be deemed withdrawn with prejudice and (B) 30 days after the Debtors withdraw or amend the Plan in a manner inconsistent with the agreed terms. F. A waiver by the Debtors’ senior management of their right to receive the first $6 million in the aggregate of any amounts earned in respect of the 2016 annual incentive compensation program and/or the 2014 long-term incentive performance plan, in each case in existence on the date hereof. G. Holders of unsecured claims against the Debtors that receive New Common Stock under the Plan will receive usual and customary minority protections, including any minority shareholder protections afforded to Senior Lenders that will be minority holders of New Common Stock under the Plan. H. A waiver by the Senior Lenders in respect of distributions on account of their deficiency claims under Arch’s pre-petition first lien credit facility, but only if the Class of Unsecured Note Claims votes to accept the Plan or, otherwise, only for the benefit of holders of unsecured note claims who voted in favor of the Plan or did not vote and either did not opt out of providing certain voluntary releases set forth in the Plan or executed the Amended and Restated RSA by the deadline on which to vote on the Plan and has not exercised any termination right thereunder. I. The obligations of the Debtors under the pre-petition first lien credit agreement to indemnify the Senior Lenders and the agents party to the pre-petition first lien credit agreement shall survive the effective date of the Plan and shall not be discharged or released pursuant to the Plan. J. The Debtors and the Senior Lenders, in consultation with the Committee, will determine whether reorganized Arch Coal will be a publicly reporting company or a privately held company upon emergence. If reorganized Arch Coal is a private company, the Plan will provide for quarterly and annual financial statements and certain current reports to be available on reorganized Arch Coal’s website. If reorganized Arch Coal is a public company, the Plan will provide for an unlisted class of common stock, equivalent to the listed stock in respect of dividends and voting and convertible into listed stock, to be available to holders not permitted to hold margin stock. K. The Board of Directors of reorganized Arch Coal, Inc. will consist of seven directors: (i) the Chief Executive Officer; and (ii) six directors selected by the Ad Hoc Committee Lenders in consultation with the Chief Executive Officer, at least one of which shall be independent. Debtor-In-Possession Financing The Company entered into an amendment to the DIP Credit Agreement, dated as of July 20, 2016 which extended the availability period to borrow under the DIP Facility from July 21, 2016 to the earlier to occur of (i) September 30, 2016 and (ii) the termination of the DIP Facility (which the Company currently expects to occur concurrently with its emergence from bankruptcy), with a corresponding extension to the period during which the 5% per annum unused commitment fee is applicable.

Supplemental Consolidating Fina

Supplemental Consolidating Financial Information	6 Months Ended
	Jun. 30, 2016
Supplemental Condensed Consolidating Financial Information [Abstract]
Supplemental Consolidating Financial Information	Supplemental Consolidating Financial Information Pursuant to the indentures governing Arch Coal, Inc.’s senior notes, certain wholly-owned subsidiaries of the Company have fully and unconditionally guaranteed the senior notes on a joint and several basis. The Company and the subsidiaries which are guarantors under the senior notes are Debtors in the Chapter 11 Cases. The following tables present condensed consolidating financial information for (i) the Company (Debtor), (ii) the issuer of the senior notes (Debtor), (iii) the guarantors under the senior notes (Debtor), and (iv) the entities which are not guarantors under the senior notes (Arch Receivable Company, LLC and the Company’s subsidiaries outside the United States) (Non-Debtors). These tables provide substantially the same information as would be presented pursuant to the disclosure requirements of ASC 852 with respect to condensed combined financial statements of entities in reorganization proceedings. Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Statements of Operations Three Months Ended June 30, 2016 Parent/Issuer Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated (In thousands) Revenues $ — $ 420,298 $ — $ — $ 420,298 Costs, expenses and other Cost of sales (exclusive of items shown separately below) 3,351 416,239 — (548 ) 419,042 Depreciation, depletion and amortization 738 57,721 — — 58,459 Amortization of acquired sales contracts, net — 1 — — 1 Change in fair value of coal derivatives and coal trading activities, net — 1,158 — — 1,158 Asset impairment and mine closure costs 3,101 40,600 — — 43,701 Selling, general and administrative expenses 12,959 5,268 1,135 (343 ) 19,019 Other operating (income) expense, net (3,455 ) (7,117 ) (880 ) 891 (10,561 ) 16,694 513,870 255 — 530,819 Loss from investment in subsidiaries (78,965 ) — — 78,965 — Loss from operations (95,659 ) (93,572 ) (255 ) 78,965 (110,521 ) Interest expense, net Interest expense (contractual interest of $100,767 for the three months ended June 30, 2016) (66,126 ) (6,607 ) (2,312 ) 29,772 (45,273 ) Interest and investment income 6,924 22,565 1,216 (29,772 ) 933 (59,202 ) 15,958 (1,096 ) — (44,340 ) Expenses related to proposed debt restructuring — — — — — Reorganization items, net (21,271 ) — — — (21,271 ) (21,271 ) — — — (21,271 ) Income (loss) from continuing operations before income taxes (176,132 ) (77,614 ) (1,351 ) 78,965 (176,132 ) Benefit from income taxes (245 ) — — — (245 ) Net loss $ (175,887 ) $ (77,614 ) $ (1,351 ) $ 78,965 $ (175,887 ) Total comprehensive loss $ (178,294 ) $ (80,467 ) $ (1,351 ) $ 81,818 $ (178,294 ) Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Statements of Operations Three Months Ended June 30, 2015 Parent/Issuer Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated (In thousands) Revenues $ — $ 644,462 $ — $ — $ 644,462 Costs, expenses and other Cost of sales (exclusive of items shown separately below) 5,908 561,191 — (847 ) 566,252 Depreciation, depletion and amortization 1,013 96,359 — — 97,372 Amortization of acquired sales contracts, net — (1,644 ) — — (1,644 ) Change in fair value of coal derivatives and coal trading activities, net — 1,211 — — 1,211 Asset impairment and mine closure costs 1,225 17,921 — — 19,146 Selling, general and administrative expenses 17,166 6,270 1,325 (493 ) 24,268 Other operating (income) expense, net (138 ) 7,483 (1,282 ) 1,340 7,403 25,174 688,791 43 — 714,008 Loss from investment in subsidiaries (30,462 ) — — 30,462 — Loss from operations (55,636 ) (44,329 ) (43 ) 30,462 (69,546 ) Interest expense, net Interest expense (119,231 ) (6,576 ) (1,127 ) 27,360 (99,574 ) Interest and investment income 6,675 20,256 1,391 (27,360 ) 962 (112,556 ) 13,680 264 — (98,612 ) Expenses related to debt restructuring (4,016 ) — — — (4,016 ) Income (loss) from continuing operations before income taxes (172,208 ) (30,649 ) 221 30,462 (172,174 ) Provision for (benefit from) income taxes (4,105 ) — 34 — (4,071 ) Net income (loss) $ (168,103 ) $ (30,649 ) $ 187 $ 30,462 $ (168,103 ) Total comprehensive income (loss) $ (167,887 ) $ (30,811 ) $ 187 $ 30,624 $ (167,887 ) Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Statements of Operations Six Months Ended June 30, 2016 Parent/Issuer Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated (In thousands) Revenues $ — $ 848,404 $ — $ — $ 848,404 Costs, expenses and other Cost of sales (exclusive of items shown separately below) 5,537 833,916 — (1,095 ) 838,358 Depreciation, depletion and amortization 1,494 120,664 — — 122,158 Amortization of acquired sales contracts, net — (832 ) — — (832 ) Change in fair value of coal derivatives and coal trading activities, net — 2,368 — — 2,368 Asset impairment and mine closure costs 6,330 122,891 — — 129,221 Selling, general and administrative expenses 26,497 10,651 2,407 (710 ) 38,845 Other operating (income) expense, net (4,552 ) (8,268 ) (1,766 ) 1,805 (12,781 ) 35,306 1,081,390 641 — 1,117,337 Loss from investment in subsidiaries (202,953 ) — — 202,953 — Loss from operations (238,259 ) (232,986 ) (641 ) 202,953 (268,933 ) Interest expense, net Interest expense (contractual interest of $199,332 for the six months ended June 30, 2016) (132,365 ) (12,973 ) (4,541 ) 60,155 (89,724 ) Interest and investment income 14,034 45,858 2,334 (60,155 ) 2,071 (118,331 ) 32,885 (2,207 ) — (87,653 ) Expenses related to proposed debt restructuring (2,213 ) — — — (2,213 ) Reorganization items, net (25,146 ) — — — (25,146 ) (27,359 ) — — — (27,359 ) Loss from continuing operations before income taxes (383,949 ) (200,101 ) (2,848 ) 202,953 (383,945 ) Provision for (benefit from) income taxes (1,360 ) — 4 — (1,356 ) Net loss $ (382,589 ) $ (200,101 ) $ (2,852 ) $ 202,953 $ (382,589 ) Total comprehensive loss $ (384,136 ) $ (203,956 ) $ (2,852 ) $ 206,808 $ (384,136 ) Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Statements of Operations Six Months Ended June 30, 2015 Parent/Issuer Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated (In thousands) Revenues $ — $ 1,321,467 $ — $ — $ 1,321,467 Costs, expenses and other Cost of sales (exclusive of items shown separately below) 13,378 1,116,877 — (1,681 ) 1,128,574 Depreciation, depletion and amortization 2,073 200,171 2 — 202,246 Amortization of acquired sales contracts, net — (5,034 ) — — (5,034 ) Change in fair value of coal derivatives and coal trading activities, net — 2,431 — — 2,431 Asset impairment and mine closure costs 1,225 17,921 — — 19,146 Selling, general and administrative expenses 32,605 12,514 2,773 (1,019 ) 46,873 Other operating (income) expense, net 3,562 12,760 (2,533 ) 2,700 16,489 52,843 1,357,640 242 — 1,410,725 Loss from investment in subsidiaries (9,413 ) — — 9,413 — Loss from operations (62,256 ) (36,173 ) (242 ) 9,413 (89,258 ) Interest expense, net Interest expense (237,286 ) (13,340 ) (2,402 ) 54,202 (198,826 ) Interest and investment income 14,747 40,030 2,760 (54,202 ) 3,335 (222,539 ) 26,690 358 — (195,491 ) Expenses related to debt restructuring (4,016 ) — — — (4,016 ) Income (loss) from continuing operations before income taxes (288,811 ) (9,483 ) 116 9,413 (288,765 ) Provision for (benefit from) income taxes (7,513 ) — 46 — (7,467 ) Net income (loss) $ (281,298 ) $ (9,483 ) $ 70 $ 9,413 $ (281,298 ) Total comprehensive income (loss) $ (277,478 ) $ (6,405 ) $ 70 $ 6,335 $ (277,478 ) Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Balance Sheets June 30, 2016 Parent/Issuer Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations Consolidated (In thousands) Assets Cash and cash equivalents $ 207,932 $ 50,426 $ 11,456 $ — $ 269,814 Short term investments 203,417 — — — 203,417 Restricted cash — — 102,236 — 102,236 Receivables 11,935 992 136,479 (4,942 ) 144,464 Inventories — 172,698 — — 172,698 Other 22,370 26,502 2,697 — 51,569 Total current assets 445,654 250,618 252,868 (4,942 ) 944,198 Property, plant and equipment, net 6,198 3,486,927 — 428 3,493,553 Investment in subsidiaries 4,648,697 — — (4,648,697 ) — Intercompany receivables — 2,269,237 — (2,269,237 ) — Note receivable from Arch Western 675,000 — — (675,000 ) — Other 42,945 203,399 1,130 — 247,474 Total other assets 5,366,642 2,472,636 1,130 (7,592,934 ) 247,474 Total assets $ 5,818,494 $ 6,210,181 $ 253,998 $ (7,597,448 ) $ 4,685,225 Liabilities and Stockholders’ Deficit Liabilities not subject to compromise Accounts payable $ 28,774 $ 49,237 $ 32 $ — $ 78,043 Accrued expenses and other current liabilities 66,771 90,356 843 (4,942 ) 153,028 Current maturities of debt — — — — — Total current liabilities 95,545 139,593 875 (4,942 ) 231,071 Long-term debt — — — — — Intercompany payables 2,038,697 — 230,540 (2,269,237 ) — Note payable to Arch Coal — 675,000 — (675,000 ) — Asset retirement obligations 1,043 389,591 — — 390,634 Accrued pension benefits 3,795 16,058 — — 19,853 Accrued postretirement benefits other than pension 72,070 15,216 — — 87,286 Accrued workers’ compensation 16,887 102,110 — — 118,997 Other noncurrent liabilities 11,249 22,461 208 — 33,918 Total liabilities not subject to compromise 2,239,286 1,360,029 231,623 (2,949,179 ) 881,759 Liabilities subject to compromise 5,206,626 223,830 5,430,456 Total liabilities 7,445,912 1,583,859 231,623 (2,949,179 ) 6,312,215 Stockholders’ equity (deficit) (1,627,418 ) 4,626,322 22,375 (4,648,269 ) (1,626,990 ) Total liabilities and stockholders’ deficit $ 5,818,494 $ 6,210,181 $ 253,998 $ (7,597,448 ) $ 4,685,225 Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Balance Sheets December 31, 2015 Parent/Issuer Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations Consolidated (In thousands) Assets Cash and cash equivalents $ 337,646 $ 100,428 $ 12,707 $ — $ 450,781 Short term investments 200,192 — — — 200,192 Restricted cash — — 97,542 — 97,542 Receivables 12,463 3,153 124,581 (4,430 ) 135,767 Inventories — 196,720 — — 196,720 Other 18,160 38,794 969 — 57,923 Total current assets 568,461 339,095 235,799 (4,430 ) 1,138,925 Property, plant and equipment, net 7,747 3,610,869 — 413 3,619,029 Investment in subsidiaries 4,887,905 — — (4,887,905 ) — Intercompany receivables — 2,253,312 — (2,253,312 ) — Note receivable from Arch Western 675,000 — — (675,000 ) — Other 39,302 243,806 819 — 283,927 Total other assets 5,602,207 2,497,118 819 (7,816,217 ) 283,927 Total assets $ 6,178,415 $ 6,447,082 $ 236,618 $ (7,820,234 ) $ 5,041,881 Liabilities and Stockholders’ Deficit Accounts payable $ 8,495 $ 119,633 $ 3 $ — $ 128,131 Accrued expenses and other current liabilities 162,268 170,575 1,037 (4,430 ) 329,450 Current maturities of debt 5,031,603 10,750 — — 5,042,353 Total current liabilities 5,202,366 300,958 1,040 (4,430 ) 5,499,934 Long-term debt — 30,953 — — 30,953 Intercompany payables 2,043,308 — 210,005 (2,253,313 ) — Note payable to Arch Coal — 675,000 — (675,000 ) — Asset retirement obligations 1,005 395,654 — — 396,659 Accrued pension benefits 12,390 14,983 — — 27,373 Accrued postretirement benefits other than pension 79,826 19,984 — — 99,810 Accrued workers’ compensation 24,247 88,023 — — 112,270 Other noncurrent liabilities 59,976 58,847 348 — 119,171 Total liabilities 7,423,118 1,584,402 211,393 (2,932,743 ) 6,286,170 Stockholders’ equity (deficit) (1,244,703 ) 4,862,680 25,225 (4,887,491 ) (1,244,289 ) Total liabilities and stockholders’ deficit $ 6,178,415 $ 6,447,082 $ 236,618 $ (7,820,234 ) $ 5,041,881 Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Statements of Cash Flows Six Months Ended June 30, 2016 Parent/Issuer Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations Consolidated (In thousands) Cash provided by (used in) operating activities $ (102,998 ) $ 56,656 $ (13,910 ) $ — $ (60,252 ) Investing Activities Capital expenditures (26 ) (74,111 ) — — (74,137 ) Additions to prepaid royalties — (217 ) — — (217 ) Proceeds from (consideration paid for) disposals and divestitures — (3,303 ) — — (3,303 ) Purchases of marketable securities (98,750 ) — — — (98,750 ) Proceeds from sale or maturity of marketable securities and other investments 94,589 — — — 94,589 Investments in and advances to affiliates — (2,890 ) — — (2,890 ) Withdrawals (deposits) of restricted cash — — (4,695 ) — (4,695 ) Cash used in investing activities (4,187 ) (80,521 ) (4,695 ) — (89,403 ) Financing Activities Net payments on other debt (4,372 ) (5,921 ) — — (10,293 ) Expenses related to proposed debt restructuring (2,213 ) — — — (2,213 ) Debt financing costs (15,625 ) — (3,181 ) — (18,806 ) Transactions with affiliates, net (319 ) (20,216 ) 20,535 — — Cash provided by (used in) financing activities (22,529 ) (26,137 ) 17,354 — (31,312 ) Decrease in cash and cash equivalents (129,714 ) (50,002 ) (1,251 ) — (180,967 ) Cash and cash equivalents, beginning of period 337,646 100,428 12,707 — 450,781 Cash and cash equivalents, end of period $ 207,932 $ 50,426 $ 11,456 $ — $ 269,814 Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Statements of Cash Flows Six Months Ended June 30, 2015 Parent/Issuer Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations Consolidated (In thousands) Cash provided by (used in) operating activities $ (295,792 ) $ 163,345 $ 6,872 $ — $ (125,575 ) Investing Activities Capital expenditures (815 ) (98,546 ) — — (99,361 ) Additions to prepaid royalties — (409 ) — — (409 ) Proceeds from disposals and divestitures — 991 — — 991 Purchases of short term investments (161,336 ) — — — (161,336 ) Proceeds from sales of short term investments 157,729 — — — 157,729 Investments in and advances to affiliates (788 ) (4,350 ) — — (5,138 ) Change in restricted cash — — (37,885 ) — (37,885 ) Cash used in investing activities (5,210 ) (102,314 ) (37,885 ) — (145,409 ) Financing Activities — Payments on term loan (9,750 ) — — — (9,750 ) Net payments on other debt (5,973 ) (3,853 ) — — (9,826 ) Expenses related to debt restructuring (4,016 ) — — — (4,016 ) Transactions with affiliates, net 116,224 (146,968 ) 30,744 — — Cash provided by (used in) financing activities 96,485 (150,821 ) 30,744 — (23,592 ) Decrease in cash and cash equivalents (204,517 ) (89,790 ) (269 ) — (294,576 ) Cash and cash equivalents, beginning of period 572,185 150,358 11,688 — 734,231 Cash and cash equivalents, end of period $ 367,668 $ 60,568 $ 11,419 $ — $ 439,655

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial reporting and U.S. Securities and Exchange Commission regulations. In the opinion of management, all adjustments, consisting of normal, recurring accruals considered necessary for a fair presentation, have been included. Results of operations for the three and six months ended June 30, 2016 are not necessarily indicative of results to be expected for the year ending December 31, 2016 . These financial statements should be read in conjunction with the audited financial statements and related notes as of and for the year ended December 31, 2015 included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission. On August 4, 2015 the Company affected a 1-for-10 reverse stock split of its common stock. Each stockholder's percentage ownership and proportional voting power remained unchanged as a result of the reverse stock split. All applicable share data, per share amounts and related information in the Condensed Consolidated Financial Statements and notes thereto have been adjusted retroactively to give effect to the 1-for-10 reverse stock split.
Filing Under Chapter 11 of the United States Bankruptcy Code	Filing Under Chapter 11 of the United States Bankruptcy Code On January 11, 2016 (the “Petition Date”), the Company and substantially all of its wholly owned domestic subsidiaries (the “Filing Subsidiaries” and, together with Arch, the “Debtors”) filed voluntary petitions for reorganization (collectively, the “Bankruptcy Petitions”) under Chapter 11 of Title 11 of the U.S. Code (the “Bankruptcy Code”) in the United States Bankruptcy Court for the Eastern District of Missouri (the “Court”). The Debtor’s Chapter 11 Cases (collectively, the “Chapter 11 Cases”) are being jointly administered under the caption In re Arch Coal, Inc., et al. Case No. 16-40120 (lead case). Each Debtor will continue to operate its business as a “debtor in possession” under the jurisdiction of the Court and in accordance with the applicable provisions of the Bankruptcy Code and the orders of the Court. The filing of the Bankruptcy Petitions constituted an event of default that accelerated the Company's obligations under the documents governing each of its 7.00% senior notes due 2019, 9.875% senior notes due 2019, 8.00% senior secured second lien notes due 2019, 7.25% senior notes due 2020, 7.25% senior notes due 2021 (together, the “senior notes”) and senior secured first lien term loan due 2018 (the “Existing Credit Agreement”) (collectively with the senior notes, the “Debt Instruments”). Immediately after filing the Bankruptcy Petitions, the Company began notifying all known current or potential creditors of the Debtors of the bankruptcy filings. Additionally, on the Petition Date, the New York Stock Exchange (the “NYSE”) determined that the Company's stock was no longer suitable for listing pursuant to Section 8.02.01D of the NYSE continued listing standards and trading in the Company’s common stock was suspended on January 11, 2016. The Company expects that its existing common stock will be extinguished upon the Company's emergence from Chapter 11 and existing equity holders will not receive consideration in respect of their equity interests. On the Petition Date, the Debtors filed a number of motions with the Court generally designed to stabilize their operations and facilitate the Debtors’ transition into Chapter 11. Certain of these motions sought authority from the Court for the Debtors to make payments upon, or otherwise honor, certain pre-petition obligations (e.g., obligations related to certain employee wages, salaries and benefits and certain vendors and other providers essential to the Debtors’ businesses). The Court has entered orders approving the relief sought in these motions, in certain cases on an interim basis. Pursuant to Section 362 of the Bankruptcy Code, the filing of the Bankruptcy Petitions automatically stayed most actions against the Debtors, including actions to collect indebtedness incurred prior to the Petition Date or to exercise control over the Debtors’ property. Subject to certain exceptions under the Bankruptcy Code, the filing of the Debtors’ Chapter 11 Cases also automatically stayed the continuation of most legal proceedings or the filing of other actions against or on behalf of the Debtors or their property to recover on, collect or secure a claim arising prior to the Petition Date or to exercise control over property of the Debtors’ bankruptcy estates, unless and until the Court modifies or lifts the automatic stay as to any such claim. Notwithstanding the general application of the automatic stay described above, governmental authorities may determine to continue actions brought under their police and regulatory powers. As required by the Bankruptcy Code, the U.S. Trustee for the Eastern District of Missouri appointed an official committee of unsecured creditors (the “Creditors’ Committee”) on January 25, 2016. The Creditors’ Committee represents all unsecured creditors of the Debtors and has a right to be heard on all matters that come before the Court. For periods subsequent to filing the Bankruptcy Petitions, the Company will apply the Financial Accounting Standards Board ("FASB") Accounting Standards Codification ("ASC") 852, "Reorganizations", in preparing its consolidated financial statements. ASC 852 requires that financial statements distinguish transactions and events that are directly associated with the reorganization from the ongoing operations of the business. Accordingly, certain revenues, expenses, realized gains and losses and provisions for losses that are realized or incurred in the bankruptcy proceedings have been recorded in a reorganization line item on the Condensed Consolidated Statement of Operations. In addition, the pre-petition obligations that may be impacted by the bankruptcy reorganization process have been classified on the balance sheet as liabilities subject to compromise. These liabilities are reported as the amounts expected to be allowed by the Court, even if they may be settled for lesser amounts. Restructuring Support Agreement As previously disclosed, prior to the Petition Date, certain of the Debtors entered into a Restructuring Support Agreement, dated as of January 10, 2016, which agreement was amended (on February 25, 2016, March 28, 2016, April 26, 2016, May 5, 2016, June 10, 2016 and June 23, 2016). On July 5, 2016, the Debtors entered into an Amended and Restated Restructuring Support Agreement (the “Amended and Restated RSA”) with lenders holding more than 75% of the aggregate principal amount of loans outstanding under Arch’s pre-petition first lien credit facility, the statutory committee of unsecured creditors appointed in the Chapter 11 Cases pursuant to Section 1102 of the Bankruptcy Code (the “Committee”) and certain members of the Committee. See Note 18, "Subsequent Events." Approval of the Disclosure Statement; Solicitation of Votes on the Plan; Confirmation Hearing On July 6, 2016, the Company filed its Third Amended Joint Plan of Reorganization Under Chapter 11 of the Bankruptcy Code (the “Third Amended Plan”) and its Disclosure Statement for the Third Amended Plan. On July 8, 2016, the Court entered an order authorizing the Company to solicit acceptances to the Third Amended Plan, setting a voting deadline of August 31, 2016 and scheduling a Confirmation Hearing with respect to the Third Amended Plan on September 13, 2016. Debtor-In-Possession Financing On January 21, 2016, the Superpriority Secured Debtor-in-Possession Credit Agreement (as amended on March 4, 2016, March 28, 2016, April 26, 2016, June 10, 2016 and June 23, 2016, the “DIP Credit Agreement”) was entered into by and among the Company, as borrower, certain of the Debtors, as guarantors (the “Guarantors” and, together with the Company, the “Loan Parties”), the lenders from time to time party thereto (the “DIP Lenders”) and Wilmington Trust, National Association, as administrative agent and collateral agent for the DIP Lenders (in such capacities, the “DIP Agent”). The DIP Credit Agreement, which has been approved by the Court on a final basis, provides for a super-priority senior secured debtor-in-possession credit facility (the “DIP Facility”) consisting of term loans (collectively, the “DIP Term Loan”) in the aggregate principal amount of up to $275 million . The maturity date of the DIP Facility is the earliest of (i) January 31, 2017, (ii) the date of the substantial consummation of a plan of reorganization that is confirmed pursuant to an order of the Court, (iii) the consummation of the sale of all or substantially all of the assets of the Loan Parties pursuant to Section 363 of the Bankruptcy Code and (iv) the date the obligations under the DIP Facility are accelerated pursuant to the terms of the DIP Credit Agreement. Borrowings under the DIP Facility bear interest at an interest rate per annum equal to, at the Company’s option (i) LIBOR plus 9.00% , subject to a 1.00% LIBOR floor or (ii) the base rate plus 8.00% . At a hearing held on February 23, 2016 in the Chapter 11 Cases, the Court issued an order approving the DIP Facility on a final basis (the "Final Order"), overruling the objections of the Creditors’ Committee and certain other parties who asserted, among other things, that the DIP Facility was unnecessary and argued that the Debtors should enter into an alternate debtor-in-possession financing facility proposed by certain members of the Creditors’ Committee. The Company entered into an amendment to the DIP Credit Agreement, dated as of July 20, 2016. See Note 18, "Subsequent Events." Securitization Agreement On January 13, 2016, the Company agreed with its securitization financing providers (the “Securitization Financing Providers”) that, subject to certain amendments (the “Amendments”), they will continue the $200 million trade accounts receivable securitization facility provided to Arch Receivable Company, LLC, a non-debtor special-purpose entity that is a wholly owned subsidiary of the Company (“Arch Receivable”) (the “Securitization Facility”). Pursuant to the Amendments, which have been approved by the Court on a final basis, the Debtors agreed to a revised schedule of fees payable to the administrator and the Securitization Financing Providers. The cost of an advance backstopping a letter of credit issued under the Securitization Facility is determined by two factors: (a) a program fee of 2.65% per year and payable on each settlement date to each Securitization Financing Provider deemed to have made such an advance and (b) the “discount,” which is calculated based on each Securitization Financing Provider’s costs, including its cost of the issuance and placement of short term promissory notes to fund such an advance. On May 9, 2016, the Securitization Facility was amended to exclude account receivables in respect of certain disposed mining operations of one of the Debtors and to effect the release of certain liens relating to such account receivables.
Going Concern	Going Concern As a result of extremely challenging current market conditions, the Company believes it will require a significant restructuring of its balance sheet in order to continue as a going concern in the long term. The Company’s ability to continue as a going concern is dependent upon, among other things, improvement in current market conditions, its ability to become profitable and maintain profitability and its ability to successfully implement its Chapter 11 plan strategy. As a result of the Bankruptcy Petitions, the realization of the Debtors’ assets and the satisfaction of liabilities are subject to significant uncertainty. While operating as a debtor-in-possession pursuant to the Bankruptcy Code, the Company may sell or otherwise dispose of or liquidate assets or settle liabilities, subject to the approval of the Court or as otherwise permitted in the ordinary course of business for amounts other than those reflected in the accompanying consolidated financial statements. Further, the Chapter 11 plan is likely to materially change the amounts and classifications of assets and liabilities reported in the Company’s Condensed Consolidated Financial Statements. The accompanying Condensed Consolidated Financial Statements have been prepared assuming that the Company will continue as a going concern. The accompanying consolidated financial statements do not include any adjustments related to the recoverability and classification of assets or the amounts and classification of liabilities that might be necessary should the Company be unable to continue as a going concern.
New Accounting Pronouncements	In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update No. 2015-03 (“ASU 2015-03”), Simplifying the Presentation of Debt Issuance Costs. ASU 2015-03 requires debt issuance costs related to a recognized debt liability to be presented in the balance sheet as a direct deduction from the carrying amount of that liability, consistent with debt discounts. The Company adopted ASU 2015-03 in the first quarter of 2016 as mandated by the standard. Previously reported "other current assets" and "current maturities of debt" have been revised to reflect the retrospective application of the standard.

Accounting Policies (Tables)

Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2016
Accounting Policies [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles	The following reflects the retrospective application: December 31, 2015 (in thousands) Other current assets, prior to revision $ 104,723 Revision of debt issuance costs (64,857 ) Other current assets, as revised $ 39,866 Current maturities of debt, prior to revision $ 5,107,210 Revision of debt issuance costs (64,857 ) Current maturities of debt, as revised $ 5,042,353

Accumulated Other Comprehensi29

Accumulated Other Comprehensive Income (Tables)	6 Months Ended
	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following items are included in accumulated other comprehensive income ("AOCI"): Pension, Postretirement and Other Accumulated Post- Other Derivative Employment Available-for- Comprehensive Instruments Benefits Sale Securities Income (In thousands) Balance at December 31, 2015 $ 325 $ (721 ) $ (1,419 ) $ (1,815 ) Unrealized gains (losses) (65 ) — 507 442 Amounts reclassified from AOCI (240 ) (3,606 ) 1,857 (1,989 ) Balance at June 30, 2016 $ 20 $ (4,327 ) $ 945 $ (3,362 )
Schedule of Comprehensive Income Reclassifications	The following amounts were reclassified out of AOCI: Amounts Reclassified from AOCI Line Item in the Condensed Consolidated Statement of Operations Three Months Ended June 30, Six Months Ended June 30, Details About AOCI Components 2016 2015 2016 2015 (In thousands) Derivative instruments $ 96 $ 2,727 $ 321 $ 3,208 Revenues — (983 ) (81 ) (1,157 ) Benefit from income taxes $ 96 $ 1,744 $ 240 $ 2,051 Net of tax Pension, postretirement and other post-employment benefits Amortization of prior service credits (1) $ 2,672 $ 2,083 $ 5,344 $ 4,167 Amortization of actuarial gains (losses), net (1) 77 (5,556 ) (1,257 ) (7,934 ) 2,749 (3,473 ) 4,087 (3,767 ) — 1,251 (481 ) 1,356 Benefit from income taxes $ 2,749 $ (2,222 ) $ 3,606 $ (2,411 ) Net of tax Available-for-sale securities $ — $ (1,430 ) $ (2,895 ) $ (4,227 ) Interest and investment income — 549 1,038 1,556 Benefit from income taxes $ — $ (881 ) $ (1,857 ) $ (2,671 ) Net of tax 1 Production-related benefits and workers' compensation costs are included in inventoriable production costs.

Liabilities Subject to Compro30

Liabilities Subject to Compromise (Tables)	6 Months Ended
	Jun. 30, 2016
Reorganizations [Abstract]
Liabilities Subject to Compromise	Liabilities subject to compromise consists of the following: June 30, 2016 (in thousands) Previously Reported Balance Sheet Line Debt $ 5,063,095 Accrued expenses and current liabilities 205,568 Accounts payable 100,047 Noncurrent liabilities 56,114 Accrued pension benefits 5,632 Total Liabilities Subject to Compromise $ 5,430,456 The debt balance included above is net of debt issuance costs of $64.9 million ; for additional information on debt, see Note 11, "Debt and Financing Arrangements."

Inventories (Tables)

Inventories (Tables)	6 Months Ended
	Jun. 30, 2016
Inventory Disclosure [Abstract]
Inventories	Inventories consist of the following: June 30, December 31, 2016 2015 (In thousands) Coal $ 61,874 $ 85,043 Repair parts and supplies 110,824 111,677 $ 172,698 $ 196,720

Investments in Available-for-32

Investments in Available-for-Sale Securities (Tables)	6 Months Ended
	Jun. 30, 2016
Available-for-sale Securities [Abstract]
Available-for-sale Securities	The Company's investments in available-for-sale marketable securities are as follows: June 30, 2016 Balance Sheet Classification Gross Unrealized Fair Short-Term Other Cost Basis Gains Losses Value Investments Assets (In thousands) Available-for-sale: U.S. government and agency securities $ 47,392 $ 120 $ — $ 47,512 $ 47,512 $ — Corporate notes and bonds 155,952 38 (85 ) 155,905 155,905 — Equity securities 1,165 1,064 — 2,229 — 2,229 Total Investments $ 204,509 $ 1,222 $ (85 ) $ 205,646 $ 203,417 $ 2,229 December 31, 2015 Balance Sheet Classification Gross Unrealized Fair Short-Term Other Cost Basis Gains Losses Value Investments Assets (In thousands) Available-for-sale: U.S. government and agency securities $ 10,007 $ — $ (12 ) $ 9,995 $ 9,995 $ — Corporate notes and bonds 190,496 — (299 ) 190,197 190,197 — Equity securities 3,938 668 (2,888 ) 1,718 — 1,718 Total Investments $ 204,441 $ 668 $ (3,199 ) $ 201,910 $ 200,192 $ 1,718

Derivatives (Tables)

Derivatives (Tables)	6 Months Ended
	Jun. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Price Risk Derivatives	At June 30, 2016 , the Company held derivatives for risk management purposes that are expected to settle in the following years: (Tons in thousands) 2016 2017 Total Coal sales 265 480 745 Coal purchases 165 — 165
Disclosure of Fair Value of Derivatives	The fair value and location of derivatives reflected in the accompanying Condensed Consolidated Balance Sheets are as follows: June 30, 2016 December 31, 2015 Fair Value of Derivatives Asset Liability Asset Liability (In thousands) Derivative Derivative Derivative Derivative Derivatives Designated as Hedging Instruments Coal $ 4 $ (50 ) $ 4 $ (20 ) Derivatives Not Designated as Hedging Instruments Heating oil -- diesel purchases 4,266 — 1,017 — Coal -- held for trading purposes 46,401 (43,798 ) 110,653 (104,814 ) Coal -- risk management 1,306 (438 ) 3,912 (1,947 ) Natural gas 190 — 494 (247 ) Foreign currency 323 — — — Total 52,486 (44,236 ) 116,076 (107,008 ) Total derivatives 52,490 (44,286 ) 116,080 (107,028 ) Effect of counterparty netting (43,810 ) 43,810 (107,028 ) 107,028 Net derivatives as classified in the balance sheets $ 8,680 $ (476 ) $ 8,204 $ 9,052 $ — $ 9,052 June 30, 2016 December 31, 2015 Net derivatives as reflected on the balance sheets (in thousands) Heating oil and foreign currency Other current assets $ 4,589 $ 1,017 Coal and natural gas Coal derivative assets 4,091 8,035 Accrued expenses and other current liabilities (476 ) — $ 8,204 $ 9,052
Effects of Derivatives on Measures of Financial Performance	The effects of derivatives on measures of financial performance are as follows: Derivatives used in Cash Flow Hedging Relationships (in thousands) Three Months Ended June 30, Gain (Loss) Recognized in Other Comprehensive Income(Effective Portion) Gains (Losses) Reclassified from Other Comprehensive Income into Income (Effective Portion) 2016 2015 2016 2015 Coal sales (1) $ (73 ) $ (1,163 ) $ 157 $ 4,990 Coal purchases (2) 6 687 (61 ) (2,263 ) Totals $ (67 ) $ (476 ) $ 96 $ 2,727 No ineffectiveness or amounts excluded from effectiveness testing relating to the Company’s cash flow hedging relationships were recognized in the results of operations in the three month periods ended June 30, 2016 and 2015 . Derivatives Not Designated as Hedging Instruments (in thousands) Three Months Ended June 30, Gain (Loss) Recognized 2016 2015 Coal — unrealized (3) $ 19 $ (875 ) Coal — realized (4) $ (180 ) $ 826 Natural gas — unrealized (3) $ 235 $ (221 ) Heating oil — diesel purchases (4) $ 2,039 $ 628 Foreign currency (4) $ 34 $ — ____________________________________________________________ Location in statement of operations: (1) — Revenues (2) — Cost of sales (3) — Change in fair value of coal derivatives and coal trading activities, net (4) — Other operating (income) expense, net Derivatives used in Cash Flow Hedging Relationships (in thousands) Six Months Ended June 30, Gain (Loss) Recognized in Other Comprehensive Income(Effective Portion) Gains (Losses) Reclassified from Other Comprehensive Income into Income 2016 2015 2016 2015 Coal sales (1) $ (60 ) $ 9,102 $ 1,526 $ 5,872 Coal purchases (2) (5 ) (4,051 ) (1,205 ) (2,664 ) Totals $ (65 ) $ 5,051 $ 321 $ 3,208 No ineffectiveness or amounts excluded from effectiveness testing relating to the Company’s cash flow hedging relationships were recognized in the results of operations in the six month periods ended June 30, 2016 and 2015 . Derivatives Not Designated as Hedging Instruments (in thousands) Six Months Ended June 30, Gain (Loss) Recognized 2016 2015 Coal — unrealized (3) $ (1,096 ) $ (1,286 ) Coal — realized (4) $ (343 ) $ 1,917 Natural gas — unrealized (3) $ (384 ) $ (62 ) Heating oil — diesel purchases (4) $ 1,596 $ (1,737 ) Foreign currency (4) $ (137 ) $ — ____________________________________________________________ Location in statement of operations: (1) — Revenues (2) — Cost of sales (3) — Change in fair value of coal derivatives and coal trading activities, net (4) — Other operating (income) expense, net

Accrued Expenses and Other Cu34

Accrued Expenses and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2016
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued expenses and other current liabilities consist of the following: June 30, December 31, 2016 2015 (In thousands) Payroll and employee benefits $ 58,801 $ 58,423 Taxes other than income taxes 97,445 104,755 Interest 162,506 119,785 Acquired sales contracts — 3,852 Workers’ compensation 13,576 16,875 Asset retirement obligations 17,297 13,795 Other 8,971 11,965 $ 358,596 $ 329,450 Less: liabilities subject to compromise (205,568 ) — $ 153,028 $ 329,450

Debt and Financing Arrangemen35

Debt and Financing Arrangements (Tables)	6 Months Ended
	Jun. 30, 2016
Debt Disclosure [Abstract]
Debt	June 30, December 31, 2016 2015 (In thousands) Term loan due 2018 ($1.9 billion face value) $ 1,875,429 $ 1,875,429 7.00% senior notes due 2019 at par 1,000,000 1,000,000 9.875% senior notes due 2019 ($375.0 million face value) 365,600 365,600 8.00% senior secured notes due 2019 at par 350,000 350,000 7.25% senior notes due 2020 at par 500,000 500,000 7.25% senior notes due 2021 at par 1,000,000 1,000,000 Other 36,923 47,134 Debt issuance costs (64,857 ) (64,857 ) 5,063,095 5,073,306 Less: liabilities subject to compromise 5,063,095 — Less: current maturities of debt — 5,042,353 Long-term debt $ — $ 30,953

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Summary of Financial Assets and Liabilities Accounted for at Fair Value	The table below sets forth, by level, the Company’s financial assets and liabilities that are recorded at fair value in the accompanying condensed consolidated balance sheet: June 30, 2016 Total Level 1 Level 2 Level 3 (In thousands) Assets: Investments in marketable securities $ 205,646 $ 49,742 $ 155,904 $ — Derivatives 8,680 2,893 977 4,810 Total assets $ 214,326 $ 52,635 $ 156,881 $ 4,810 Liabilities: Derivatives $ 476 $ 437 $ — $ 39
Summary of Change in the Fair Values of Financial Instruments Categorized as Level 3	The following table summarizes the change in the fair values of financial instruments categorized as Level 3. Three Months Ended June 30, 2016 Six Months Ended June 30, 2016 (In thousands) Balance, beginning of period $ 2,702 $ 2,432 Realized and unrealized gains recognized in earnings, net 1,061 202 Realized and unrealized gains recognized in other comprehensive income, net — — Purchases 2,073 3,435 Issuances (255 ) (488 ) Settlements (810 ) (810 ) Ending balance $ 4,771 $ 4,771

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	6 Months Ended
	Jun. 30, 2016
Pension and Other Postretirement Benefit Expense [Abstract]
Pension Benefit Costs	The following table details the components of pension benefit costs (credits): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 (In thousands) Service cost $ — $ 1 $ — $ 5 Interest cost 3,197 3,695 6,535 7,265 Expected return on plan assets (4,444 ) (4,466 ) (8,982 ) (10,231 ) Curtailments 454 — 454 — Amortization of other actuarial losses 924 3,185 1,681 5,243 Net costs (credits) $ 131 $ 2,415 $ (312 ) $ 2,282 The following table details the components of other postretirement benefit costs (credits): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 (In thousands) Service cost $ 105 $ 200 $ 265 $ 433 Interest cost 1,138 308 2,272 643 Curtailments (970 ) — (970 ) — Amortization of prior service credits (2,672 ) (2,083 ) (5,345 ) (4,167 ) Amortization of other actuarial losses (gains) (566 ) (599 ) (1,132 ) (1,055 ) Net credit $ (2,965 ) $ (2,174 ) $ (4,910 ) $ (4,146 )

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2016
Segment Reporting [Abstract]
Schedule of Operating Segment Results	PRB APP Other Operating Segments Corporate, Other and Eliminations Consolidated (in thousands) Three Months Ended June 30, 2016 Revenues $ 207,735 $ 170,940 $ 41,623 $ — $ 420,298 Adjusted EBITDA 15,932 (5,963 ) 595 (18,924 ) (8,360 ) Depreciation, depletion and amortization 30,145 19,422 8,110 782 58,459 Amortization of acquired sales contracts, net 76 (75 ) — — 1 Capital expenditures 489 6,740 949 60,033 68,211 Three Months Ended June 30, 2015 Revenues $ 342,480 $ 224,298 $ 77,684 $ — $ 644,462 Adjusted EBITDA 56,654 11,427 7,456 (30,209 ) 45,328 Depreciation, depletion and amortization 42,711 42,203 10,834 1,624 97,372 Amortization of acquired sales contracts, net (761 ) (883 ) — — (1,644 ) Capital expenditures 4,425 7,948 1,668 62,440 76,481 Six Months Ended June 30, 2016 Revenues $ 430,857 $ 344,558 $ 72,989 $ — $ 848,404 Adjusted EBITDA 22,942 1,645 (2,732 ) (40,241 ) (18,386 ) Depreciation, depletion and amortization 62,905 41,751 16,043 1,459 122,158 Amortization of acquired sales contracts, net 30 (862 ) — — (832 ) Capital expenditures 499 10,369 2,910 60,359 74,137 Six Months Ended June 30, 2015 Revenues $ 733,686 $ 447,737 $ 140,044 $ — $ 1,321,467 Adjusted EBITDA 128,716 51,234 9,147 (61,997 ) 127,100 Depreciation, depletion and amortization 87,072 90,930 20,889 3,355 202,246 Amortization of acquired sales contracts, net (2,046 ) (2,988 ) — — (5,034 ) Capital expenditures 21,394 11,333 4,310 62,324 99,361
Reconciliation Statement of Segment Income from Operations to Consolidated Income Before Income Taxes	A reconciliation of adjusted EBITDA to consolidated loss before income taxes follows: Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 (In thousands) Adjusted EBITDA $ (8,360 ) $ 45,328 $ (18,386 ) $ 127,100 Depreciation, depletion and amortization (58,459 ) (97,372 ) (122,158 ) (202,246 ) Amortization of acquired sales contracts, net (1 ) 1,644 832 5,034 Asset impairment and mine closure costs (43,701 ) (19,146 ) (129,221 ) (19,146 ) Interest expense, net (44,340 ) (98,612 ) (87,653 ) (195,491 ) Nonoperating expenses (21,271 ) (4,016 ) (27,359 ) (4,016 ) Loss before income taxes $ (176,132 ) $ (172,174 ) $ (383,945 ) $ (288,765 )

Supplemental Consolidating Fi39

Supplemental Consolidating Financial Information (Tables)	6 Months Ended
	Jun. 30, 2016
Supplemental Condensed Consolidating Financial Information [Abstract]
Schedule of Condensed Consolidating Statements of Income	Condensed Consolidating Statements of Operations Three Months Ended June 30, 2016 Parent/Issuer Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated (In thousands) Revenues $ — $ 420,298 $ — $ — $ 420,298 Costs, expenses and other Cost of sales (exclusive of items shown separately below) 3,351 416,239 — (548 ) 419,042 Depreciation, depletion and amortization 738 57,721 — — 58,459 Amortization of acquired sales contracts, net — 1 — — 1 Change in fair value of coal derivatives and coal trading activities, net — 1,158 — — 1,158 Asset impairment and mine closure costs 3,101 40,600 — — 43,701 Selling, general and administrative expenses 12,959 5,268 1,135 (343 ) 19,019 Other operating (income) expense, net (3,455 ) (7,117 ) (880 ) 891 (10,561 ) 16,694 513,870 255 — 530,819 Loss from investment in subsidiaries (78,965 ) — — 78,965 — Loss from operations (95,659 ) (93,572 ) (255 ) 78,965 (110,521 ) Interest expense, net Interest expense (contractual interest of $100,767 for the three months ended June 30, 2016) (66,126 ) (6,607 ) (2,312 ) 29,772 (45,273 ) Interest and investment income 6,924 22,565 1,216 (29,772 ) 933 (59,202 ) 15,958 (1,096 ) — (44,340 ) Expenses related to proposed debt restructuring — — — — — Reorganization items, net (21,271 ) — — — (21,271 ) (21,271 ) — — — (21,271 ) Income (loss) from continuing operations before income taxes (176,132 ) (77,614 ) (1,351 ) 78,965 (176,132 ) Benefit from income taxes (245 ) — — — (245 ) Net loss $ (175,887 ) $ (77,614 ) $ (1,351 ) $ 78,965 $ (175,887 ) Total comprehensive loss $ (178,294 ) $ (80,467 ) $ (1,351 ) $ 81,818 $ (178,294 ) Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Statements of Operations Three Months Ended June 30, 2015 Parent/Issuer Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated (In thousands) Revenues $ — $ 644,462 $ — $ — $ 644,462 Costs, expenses and other Cost of sales (exclusive of items shown separately below) 5,908 561,191 — (847 ) 566,252 Depreciation, depletion and amortization 1,013 96,359 — — 97,372 Amortization of acquired sales contracts, net — (1,644 ) — — (1,644 ) Change in fair value of coal derivatives and coal trading activities, net — 1,211 — — 1,211 Asset impairment and mine closure costs 1,225 17,921 — — 19,146 Selling, general and administrative expenses 17,166 6,270 1,325 (493 ) 24,268 Other operating (income) expense, net (138 ) 7,483 (1,282 ) 1,340 7,403 25,174 688,791 43 — 714,008 Loss from investment in subsidiaries (30,462 ) — — 30,462 — Loss from operations (55,636 ) (44,329 ) (43 ) 30,462 (69,546 ) Interest expense, net Interest expense (119,231 ) (6,576 ) (1,127 ) 27,360 (99,574 ) Interest and investment income 6,675 20,256 1,391 (27,360 ) 962 (112,556 ) 13,680 264 — (98,612 ) Expenses related to debt restructuring (4,016 ) — — — (4,016 ) Income (loss) from continuing operations before income taxes (172,208 ) (30,649 ) 221 30,462 (172,174 ) Provision for (benefit from) income taxes (4,105 ) — 34 — (4,071 ) Net income (loss) $ (168,103 ) $ (30,649 ) $ 187 $ 30,462 $ (168,103 ) Total comprehensive income (loss) $ (167,887 ) $ (30,811 ) $ 187 $ 30,624 $ (167,887 )
Schedule of Condensed Consolidating Balance Sheets	Condensed Consolidating Balance Sheets June 30, 2016 Parent/Issuer Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations Consolidated (In thousands) Assets Cash and cash equivalents $ 207,932 $ 50,426 $ 11,456 $ — $ 269,814 Short term investments 203,417 — — — 203,417 Restricted cash — — 102,236 — 102,236 Receivables 11,935 992 136,479 (4,942 ) 144,464 Inventories — 172,698 — — 172,698 Other 22,370 26,502 2,697 — 51,569 Total current assets 445,654 250,618 252,868 (4,942 ) 944,198 Property, plant and equipment, net 6,198 3,486,927 — 428 3,493,553 Investment in subsidiaries 4,648,697 — — (4,648,697 ) — Intercompany receivables — 2,269,237 — (2,269,237 ) — Note receivable from Arch Western 675,000 — — (675,000 ) — Other 42,945 203,399 1,130 — 247,474 Total other assets 5,366,642 2,472,636 1,130 (7,592,934 ) 247,474 Total assets $ 5,818,494 $ 6,210,181 $ 253,998 $ (7,597,448 ) $ 4,685,225 Liabilities and Stockholders’ Deficit Liabilities not subject to compromise Accounts payable $ 28,774 $ 49,237 $ 32 $ — $ 78,043 Accrued expenses and other current liabilities 66,771 90,356 843 (4,942 ) 153,028 Current maturities of debt — — — — — Total current liabilities 95,545 139,593 875 (4,942 ) 231,071 Long-term debt — — — — — Intercompany payables 2,038,697 — 230,540 (2,269,237 ) — Note payable to Arch Coal — 675,000 — (675,000 ) — Asset retirement obligations 1,043 389,591 — — 390,634 Accrued pension benefits 3,795 16,058 — — 19,853 Accrued postretirement benefits other than pension 72,070 15,216 — — 87,286 Accrued workers’ compensation 16,887 102,110 — — 118,997 Other noncurrent liabilities 11,249 22,461 208 — 33,918 Total liabilities not subject to compromise 2,239,286 1,360,029 231,623 (2,949,179 ) 881,759 Liabilities subject to compromise 5,206,626 223,830 5,430,456 Total liabilities 7,445,912 1,583,859 231,623 (2,949,179 ) 6,312,215 Stockholders’ equity (deficit) (1,627,418 ) 4,626,322 22,375 (4,648,269 ) (1,626,990 ) Total liabilities and stockholders’ deficit $ 5,818,494 $ 6,210,181 $ 253,998 $ (7,597,448 ) $ 4,685,225 Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Balance Sheets December 31, 2015 Parent/Issuer Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations Consolidated (In thousands) Assets Cash and cash equivalents $ 337,646 $ 100,428 $ 12,707 $ — $ 450,781 Short term investments 200,192 — — — 200,192 Restricted cash — — 97,542 — 97,542 Receivables 12,463 3,153 124,581 (4,430 ) 135,767 Inventories — 196,720 — — 196,720 Other 18,160 38,794 969 — 57,923 Total current assets 568,461 339,095 235,799 (4,430 ) 1,138,925 Property, plant and equipment, net 7,747 3,610,869 — 413 3,619,029 Investment in subsidiaries 4,887,905 — — (4,887,905 ) — Intercompany receivables — 2,253,312 — (2,253,312 ) — Note receivable from Arch Western 675,000 — — (675,000 ) — Other 39,302 243,806 819 — 283,927 Total other assets 5,602,207 2,497,118 819 (7,816,217 ) 283,927 Total assets $ 6,178,415 $ 6,447,082 $ 236,618 $ (7,820,234 ) $ 5,041,881 Liabilities and Stockholders’ Deficit Accounts payable $ 8,495 $ 119,633 $ 3 $ — $ 128,131 Accrued expenses and other current liabilities 162,268 170,575 1,037 (4,430 ) 329,450 Current maturities of debt 5,031,603 10,750 — — 5,042,353 Total current liabilities 5,202,366 300,958 1,040 (4,430 ) 5,499,934 Long-term debt — 30,953 — — 30,953 Intercompany payables 2,043,308 — 210,005 (2,253,313 ) — Note payable to Arch Coal — 675,000 — (675,000 ) — Asset retirement obligations 1,005 395,654 — — 396,659 Accrued pension benefits 12,390 14,983 — — 27,373 Accrued postretirement benefits other than pension 79,826 19,984 — — 99,810 Accrued workers’ compensation 24,247 88,023 — — 112,270 Other noncurrent liabilities 59,976 58,847 348 — 119,171 Total liabilities 7,423,118 1,584,402 211,393 (2,932,743 ) 6,286,170 Stockholders’ equity (deficit) (1,244,703 ) 4,862,680 25,225 (4,887,491 ) (1,244,289 ) Total liabilities and stockholders’ deficit $ 6,178,415 $ 6,447,082 $ 236,618 $ (7,820,234 ) $ 5,041,881
Schedule of Condensed Consolidating Statements of Cash Flows	Condensed Consolidating Statements of Cash Flows Six Months Ended June 30, 2016 Parent/Issuer Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations Consolidated (In thousands) Cash provided by (used in) operating activities $ (102,998 ) $ 56,656 $ (13,910 ) $ — $ (60,252 ) Investing Activities Capital expenditures (26 ) (74,111 ) — — (74,137 ) Additions to prepaid royalties — (217 ) — — (217 ) Proceeds from (consideration paid for) disposals and divestitures — (3,303 ) — — (3,303 ) Purchases of marketable securities (98,750 ) — — — (98,750 ) Proceeds from sale or maturity of marketable securities and other investments 94,589 — — — 94,589 Investments in and advances to affiliates — (2,890 ) — — (2,890 ) Withdrawals (deposits) of restricted cash — — (4,695 ) — (4,695 ) Cash used in investing activities (4,187 ) (80,521 ) (4,695 ) — (89,403 ) Financing Activities Net payments on other debt (4,372 ) (5,921 ) — — (10,293 ) Expenses related to proposed debt restructuring (2,213 ) — — — (2,213 ) Debt financing costs (15,625 ) — (3,181 ) — (18,806 ) Transactions with affiliates, net (319 ) (20,216 ) 20,535 — — Cash provided by (used in) financing activities (22,529 ) (26,137 ) 17,354 — (31,312 ) Decrease in cash and cash equivalents (129,714 ) (50,002 ) (1,251 ) — (180,967 ) Cash and cash equivalents, beginning of period 337,646 100,428 12,707 — 450,781 Cash and cash equivalents, end of period $ 207,932 $ 50,426 $ 11,456 $ — $ 269,814 Arch Coal, Inc. and Subsidiaries (Debtor-in-Possession) Condensed Consolidating Statements of Cash Flows Six Months Ended June 30, 2015 Parent/Issuer Guarantor Subsidiaries Non-Guarantor Subsidiaries Eliminations Consolidated (In thousands) Cash provided by (used in) operating activities $ (295,792 ) $ 163,345 $ 6,872 $ — $ (125,575 ) Investing Activities Capital expenditures (815 ) (98,546 ) — — (99,361 ) Additions to prepaid royalties — (409 ) — — (409 ) Proceeds from disposals and divestitures — 991 — — 991 Purchases of short term investments (161,336 ) — — — (161,336 ) Proceeds from sales of short term investments 157,729 — — — 157,729 Investments in and advances to affiliates (788 ) (4,350 ) — — (5,138 ) Change in restricted cash — — (37,885 ) — (37,885 ) Cash used in investing activities (5,210 ) (102,314 ) (37,885 ) — (145,409 ) Financing Activities — Payments on term loan (9,750 ) — — — (9,750 ) Net payments on other debt (5,973 ) (3,853 ) — — (9,826 ) Expenses related to debt restructuring (4,016 ) — — — (4,016 ) Transactions with affiliates, net 116,224 (146,968 ) 30,744 — — Cash provided by (used in) financing activities 96,485 (150,821 ) 30,744 — (23,592 ) Decrease in cash and cash equivalents (204,517 ) (89,790 ) (269 ) — (294,576 ) Cash and cash equivalents, beginning of period 572,185 150,358 11,688 — 734,231 Cash and cash equivalents, end of period $ 367,668 $ 60,568 $ 11,419 $ — $ 439,655

Basis of Presentation (Narrativ

Basis of Presentation (Narrative) (Details) $ in Millions	Jan. 21, 2016USD ($)	Jan. 13, 2016USD ($)factor	Aug. 04, 2015	Jun. 30, 2016	Jan. 11, 2016	Jan. 10, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Reverse stock split, conversion ratio			0.1
Debt Instrument [Line Items]
DIP, amount arranged	$ 275
Securitized accounts receivable		$ 200
Number of factors required to determine cost of advance backstopping a letter of credit issued under the securitization facility | factor		2
Program fees		2.65%
Holder's of First Lien creditors (percent)						66.666%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	9.00%
Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	8.00%
Interest Rate Floor [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	1.00%
7.00% Senior Notes Due 2019 [Member]
Debt Instrument [Line Items]
Senior notes interest rate (percent)				7.00%	7.00%
9.875% Senior Notes Due 2019 [Member]
Debt Instrument [Line Items]
Senior notes interest rate (percent)				9.875%	9.875%
8.00% Senior Secured Notes due 2019 [Member]
Debt Instrument [Line Items]
Senior notes interest rate (percent)				8.00%	8.00%
7.25% Senior Notes Due 2020 [Member]
Debt Instrument [Line Items]
Senior notes interest rate (percent)				7.25%	7.25%
7.25% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Senior notes interest rate (percent)				7.25%	7.25%

Accounting Policies (Details)

Accounting Policies (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other current assets	$ 39,741	$ 39,866
Debt issuance costs	64,857	64,857
Current maturities of debt	$ 0	5,042,353
Scenario, Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other current assets		104,723
Current maturities of debt		5,107,210
Accounting Standards Update 03-2015 [Member] | Other Current Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt issuance costs		(64,857)
Accounting Standards Update 03-2015 [Member] | Long-term Debt, Current [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt issuance costs		$ 64,857

Accumulated Other Comprehensi42

Accumulated Other Comprehensive Income (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2016USD ($)
Accumulated Other Comprenhensive Income (Loss) [Roll Forward]
Beginning Balance	$ (1,815)
Ending Balance	(3,362)
Derivative Instruments [Member]
Accumulated Other Comprenhensive Income (Loss) [Roll Forward]
Beginning Balance	325
Unrealized gains (losses)	(65)
Amounts reclassified from AOCI	(240)
Ending Balance	20
Pension, Postretirement and Other Postemployment Benefits [Member]
Accumulated Other Comprenhensive Income (Loss) [Roll Forward]
Beginning Balance	(721)
Unrealized gains (losses)	0
Amounts reclassified from AOCI	(3,606)
Ending Balance	(4,327)
Available-for-Sale Securities [Member]
Accumulated Other Comprenhensive Income (Loss) [Roll Forward]
Beginning Balance	(1,419)
Unrealized gains (losses)	507
Amounts reclassified from AOCI	1,857
Ending Balance	945
AOCI Attributable to Parent [Member]
Accumulated Other Comprenhensive Income (Loss) [Roll Forward]
Beginning Balance	(1,815)
Unrealized gains (losses)	442
Amounts reclassified from AOCI	(1,989)
Ending Balance	$ (3,362)

Accumulated Other Comprehensi43

Accumulated Other Comprehensive Income (Schedule of Reclassifications) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Revenues	$ 420,298	$ 644,462	$ 848,404	$ 1,321,467
Benefit from income taxes	245	4,071	1,356	7,467
Net loss	(175,887)	(168,103)	(382,589)	(281,298)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Derivative Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Revenues	96	2,727	321	3,208
Benefit from income taxes	0	(983)	(81)	(1,157)
Net loss	96	1,744	240	2,051
Reclassification out of Accumulated Other Comprehensive Income [Member] | Pension, Postretirement and Other Postemployment Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of prior service credits	2,672	2,083	5,344	4,167
Amortization of actuarial gains (losses), net	77	(5,556)	(1,257)	(7,934)
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, before Tax	2,749	(3,473)	4,087	(3,767)
Benefit from income taxes	0	1,251	(481)	1,356
Net of tax	2,749	(2,222)	3,606	(2,411)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Benefit from income taxes	0	549	1,038	1,556
Net loss	0	(881)	(1,857)	(2,671)
Interest and investment income	$ 0	$ (1,430)	$ (2,895)	$ (4,227)

Reorganization items, net (Narr

Reorganization items, net (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Discontinued Operations and Disposal Groups [Abstract]
Reorganization items, net	$ (21,271)	$ 0	$ (25,146)	$ 0
Professional fee expense	(22,300)		(40,000)
Non-cash gains on rejected contracts	1,000		14,900
Payments for reorganization items	$ 13,600		$ 15,100

Liabilities Subject to Compro45

Liabilities Subject to Compromise (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Debt	$ 5,063,095	$ 0
Accrued expenses and current liabilities	205,568
Accounts payable	100,047
Noncurrent liabilities	56,114
Accrued pension benefits	5,632
Liabilities Subject to Compromise	5,430,456	0
Debt issuance costs	$ 64,857	$ 64,857

Asset Impairments and Mine Cl46

Asset Impairments and Mine Closure Costs (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Restructuring Cost and Reserve [Line Items]
Asset impairment and mine closure costs	$ 43,701	$ 85,500	$ 19,146	$ 129,221	$ 19,146
Impairment charge on investment		2,900
Curtailments	3,600
Severance expense	2,100	5,100
Longview, Washington [Member]
Restructuring Cost and Reserve [Line Items]
Impairment charge on investment	$ 38,000
Kentucky [Member]
Restructuring Cost and Reserve [Line Items]
Impaired coal reserves and surface land		74,100
Cumberland River [Member]
Restructuring Cost and Reserve [Line Items]
Impairment charge			5,600
Royalty Agreements [Member]
Restructuring Cost and Reserve [Line Items]
Impairment charge		$ 3,400
Royalty Agreements [Member] | Mountain Laurel, Spruce and Briar Branch [Member]
Restructuring Cost and Reserve [Line Items]
Impairment charge			$ 12,200

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Coal	$ 61,874	$ 85,043
Repair parts and supplies	110,824	111,677
Inventories	172,698	196,720
Allowance for slow-moving and obsolete inventories	$ 6,500	$ 6,000

Investments in Available-for-48

Investments in Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Current	$ 203,417	$ 200,192
Total Investments, Cost Basis	204,509	204,441
Total Investments, Accumulated Gross Unrealized Gains	1,222	668
Total Investments, Accumulated Gross Unrealized Losses	(85)	(3,199)
Total Investments	205,646	201,910
Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Total Investments, Current	203,417	200,192
Other Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Total Investments, Noncurrent	2,229	1,718
US Government and Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Cost Basis	47,392	10,007
Debt Securities, Accumulated Gross Unrealized Gains	120	0
Debt Securities, Accumulated Gross Unrealized Losses	0	(12)
Debt Securities	47,512	9,995
US Government and Agency Securities [Member] | Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Current	47,512	9,995
US Government and Agency Securities [Member] | Other Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Noncurrent	0	0
Corporate Notes and Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Cost Basis	155,952	190,496
Debt Securities, Accumulated Gross Unrealized Gains	38	0
Debt Securities, Accumulated Gross Unrealized Losses	(85)	(299)
Debt Securities	155,905	190,197
Corporate Notes and Bonds [Member] | Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Current	155,905	190,197
Corporate Notes and Bonds [Member] | Other Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt Securities, Noncurrent	0	0
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity Securities, Cost Basis	1,165	3,938
Equity Securities, Accumulated Gross Unrealized Gains	1,064	668
Equity Securities, Accumulated Gross Unrealized Losses	0	(2,888)
Equity securities	2,229	1,718
Equity Securities [Member] | Short-term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity Securities, Current	0	0
Equity Securities [Member] | Other Assets [Member]
Schedule of Available-for-sale Securities [Line Items]
Equity Securities, Noncurrent	$ 2,229	$ 1,718

Investments in Available-for-49

Investments in Available-for-Sale Securities (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Available-for-sale Securities [Abstract]
Unrealized losses owned for less than 12 months		$ 73.5	$ 184.6
Unrealized losses owned for greater than 12 months		$ 35.7	$ 15.8
Other-than-temporary-impairment charge on an available-for-sale security	$ 2.9

Derivatives (Narrative) (Detail

Derivatives (Narrative) (Details) gal in Millions, $ in Millions	3 Months Ended		6 Months Ended		9 Months Ended
	Jun. 30, 2016USD ($)gal$ / option	Jun. 30, 2015USD ($)	Jun. 30, 2016USD ($)gal$ / option	Jun. 30, 2015USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2017$ / option	Dec. 31, 2015USD ($)
Derivative [Line Items]
Current liability for the obligation to return cash collateral | $	$ 0.3		$ 0.3				$ 1.7
Net unrealized and realized gains (losses) related to trading portfolio | $	$ 1	$ 0.1	$ 1	$ 1.1
Scenario, Forecast [Member]
Derivative [Line Items]
Value of trading portfolio realized | $					$ 2.7
Not Designated as Hedging Instrument [Member] | Heating Oil [Member]
Derivative [Line Items]
Percent of expected requirements covered	49.00%		49.00%
Derivative, average price risk option strike price | $ / option	1.32		1.32
Quantities under derivative contracts	9.8		9.8
Not Designated as Hedging Instrument [Member] | Diesel Purchases [Member]
Derivative [Line Items]
Percent of expected requirements covered	62.00%		62.00%
Derivative, average price risk option strike price | $ / option	2.25		2.25
Not Designated as Hedging Instrument [Member] | Diesel Purchases [Member] | Scenario, Forecast [Member]
Derivative [Line Items]
Percent of expected requirements covered						18.00%
Derivative, average price risk option strike price | $ / option						1.60
Not Designated as Hedging Instrument [Member] | Diesel Purchases [Member] | Heating Oil [Member]
Derivative [Line Items]
Quantities under derivative contracts	20		20
Not Designated as Hedging Instrument [Member] | Diesel Purchases [Member] | Minimum [Member]
Derivative [Line Items]
Gallons of diesel fuel purchased annually			41
Not Designated as Hedging Instrument [Member] | Diesel Purchases [Member] | Maximum [Member]
Derivative [Line Items]
Gallons of diesel fuel purchased annually			46

Derivatives (Schedule of Price

Derivatives (Schedule of Price Risk Derivatives) (Details) T in Thousands	Jun. 30, 2016T
Coal sales [Member]
Derivative [Line Items]
Derivatives Held	745
Coal purchases [Member]
Derivative [Line Items]
Derivatives Held	165
2016 [Member] | Coal sales [Member]
Derivative [Line Items]
Derivatives Held	265
2016 [Member] | Coal purchases [Member]
Derivative [Line Items]
Derivatives Held	165
2017 [Member] | Coal sales [Member]
Derivative [Line Items]
Derivatives Held	480
2017 [Member] | Coal purchases [Member]
Derivative [Line Items]
Derivatives Held	0

Derivatives (Disclosure Of Fair

Derivatives (Disclosure Of Fair Value Of Derivatives) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Liability	$ (43,810)	$ (107,028)
Derivative Liability, Fair Value, Gross Asset	43,810	107,028
Derivative Asset	8,680	9,052
Derivative Liability	(476)	0
Net derivatives as classified in the balance sheet	8,204	9,052
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Price Risk Derivative Instruments Not Designated as Hedging Instruments Asset, at Fair Value	52,486	116,076
Price Risk Derivative Instruments Not Designated as Hedging Instruments Liability, at Fair Value	(44,236)	(107,008)
Not Designated as Hedging Instrument [Member] | Coal Contract [Member]
Derivative [Line Items]
Derivative Assets	46,401	110,653
Derivative Liabilities	(43,798)	(104,814)
Heating Oil-Diesel Purchases [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Price Risk Derivative Instruments Not Designated as Hedging Instruments Asset, at Fair Value	4,266	1,017
Price Risk Derivative Instruments Not Designated as Hedging Instruments Liability, at Fair Value	0	0
Coal Contract [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Assets	4	4
Derivative Liabilities	(50)	(20)
Coal Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Price Risk Derivative Instruments Not Designated as Hedging Instruments Asset, at Fair Value	1,306	3,912
Price Risk Derivative Instruments Not Designated as Hedging Instruments Liability, at Fair Value	(438)	(1,947)
Natural Gas [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Price Risk Derivative Instruments Not Designated as Hedging Instruments Asset, at Fair Value	190	494
Price Risk Derivative Instruments Not Designated as Hedging Instruments Liability, at Fair Value	0	(247)
Foreign Currency [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Price Risk Derivative Instruments Not Designated as Hedging Instruments Asset, at Fair Value	323	0
Price Risk Derivative Instruments Not Designated as Hedging Instruments Liability, at Fair Value	0	0
Price Risk Derivative [Member]
Derivative [Line Items]
Derivative Assets	52,490	116,080
Derivative Liabilities	$ (44,286)	$ (107,028)

Derivatives (Net Derivatives As

Derivatives (Net Derivatives As Reflected On The Balance Sheets) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	$ 8,204	$ 9,052
Heating Oil [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	4,589	1,017
Coal Contract [Member] | Coal Derivative Assets [Member]
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	4,091	8,035
Coal Contract [Member] | Accrued expenses and other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	$ (476)	$ 0

Derivatives (Effects Of Derivat

Derivatives (Effects Of Derivatives On Measures Of Financial Performance) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income(Effective Portion)	$ (67)	$ (476)	$ (65)	$ 5,051
Gains (Losses) Reclassified from Other Comprehensive Income into Income (Effective Portion)	96	2,727	321	3,208
Designated as Hedging Instrument [Member] | Coal Contract [Member] | Coal sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income(Effective Portion)	(73)	(1,163)	(60)	9,102
Designated as Hedging Instrument [Member] | Coal Contract [Member] | Coal sales [Member] | Sales Revenue, Net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Reclassified from Other Comprehensive Income into Income (Effective Portion)	157	4,990	1,526	5,872
Designated as Hedging Instrument [Member] | Coal Contract [Member] | Coal purchases [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income(Effective Portion)	6	687	(5)	(4,051)
Designated as Hedging Instrument [Member] | Coal Contract [Member] | Coal purchases [Member] | Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) Reclassified from Other Comprehensive Income into Income (Effective Portion)	(61)	(2,263)	(1,205)	(2,664)
Not Designated as Hedging Instrument [Member] | Coal Contract [Member] | Change in Fair Value of Coal Derivatives and Coal Trading Activity, Net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives	19	(875)	(1,096)	(1,286)
Not Designated as Hedging Instrument [Member] | Coal Contract [Member] | Other Operating Income (Expense) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives	(180)	826	(343)	1,917
Not Designated as Hedging Instrument [Member] | Natural Gas [Member] | Change in Fair Value of Coal Derivatives and Coal Trading Activity, Net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives	235	(221)	(384)	(62)
Not Designated as Hedging Instrument [Member] | Heating Oil-Diesel Purchases [Member] | Other Operating Income (Expense) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Heating oil realized and unrealized gains and losses	2,039	628	1,596	(1,737)
Not Designated as Hedging Instrument [Member] | Foreign Currency [Member] | Other Operating Income (Expense) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Heating oil realized and unrealized gains and losses	$ 34	$ 0	$ (137)	$ 0

Accrued Expenses and Other Cu55

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Payroll and employee benefits	$ 58,801	$ 58,423
Taxes other than income taxes	97,445	104,755
Interest	162,506	119,785
Acquired sales contracts	0	3,852
Workers’ compensation	13,576	16,875
Asset retirement obligations	17,297	13,795
Other	8,971	11,965
Accrued Liabilities, Current, Not Subject To Compromise	358,596	329,450
Less: liabilities subject to compromise	(205,568)	0
Accrued Liabilities, Current	$ 153,028	$ 329,450

Debt and Financing Arrangemen56

Debt and Financing Arrangements - Long term Debt (Details) - USD ($)	Jun. 30, 2016	Jan. 11, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Other	$ 36,923,000		$ 47,134,000
Debt issuance costs	(64,857,000)		(64,857,000)
Total	5,063,095,000		5,073,306,000
Less: liabilities subject to compromise	5,063,095,000		0
Less: current maturities of debt	0		5,042,353,000
Long-term debt	0		30,953,000
Loans Payable [Member]
Debt Instrument [Line Items]
Term loan due 2018 ($1.9 billion face value)	1,875,429,000		1,875,429,000
Debt instrument, face amount	1,900,000,000		1,900,000,000
7.00% Senior Notes Due 2019 [Member]
Debt Instrument [Line Items]
Senior notes	$ 1,000,000,000		1,000,000,000
Senior notes interest rate (percent)	7.00%	7.00%
9.875% Senior Notes Due 2019 [Member]
Debt Instrument [Line Items]
Senior notes	$ 365,600,000		365,600,000
Senior notes interest rate (percent)	9.875%	9.875%
Debt instrument, face amount	$ 375,000,000		375,000,000
8.00% Senior Notes Due 2019 [Member]
Debt Instrument [Line Items]
Senior notes	$ 350,000,000		350,000,000
Senior notes interest rate (percent)	8.00%
7.25% Senior Notes Due 2020 [Member]
Debt Instrument [Line Items]
Senior notes	$ 500,000,000		500,000,000
Senior notes interest rate (percent)	7.25%	7.25%
7.25% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Senior notes	$ 1,000,000,000		$ 1,000,000,000
Senior notes interest rate (percent)	7.25%	7.25%

Debt and Financing Arrangemen57

Debt and Financing Arrangements - Narrative (Details)	Jan. 21, 2016USD ($)	Jan. 13, 2016USD ($)factor	Jun. 30, 2016USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2015USD ($)	Jul. 20, 2016USD ($)	Jan. 11, 2016
Line of Credit Facility [Line Items]
Securitized accounts receivable		$ 200,000,000
Number of factors required to determine cost of advance backstopping a letter of credit issued under the securitization facility | factor		2
Program fees		2.65%
DIP, amount arranged	$ 275,000,000
DIP, Carve-out for claims	75,000,000
DIP, prior to entry of final order	300,000,000
DIP, following the entry of final order	500,000,000
DIP, customary prepayments, proceeds from sale or disposition of non-ordinary course asset	50,000,000
DIP, customary prepayments, proceeds from sale or disposition of non-ordinary course asset, individual sale, maximum	7,500,000
DIP, customary prepayments, proceeds from any casualty event	$ 50,000,000
Interest expense			$ (45,273,000)	$ (99,574,000)	$ (89,724,000)	$ (198,826,000)
Subsequent Event [Member]
Line of Credit Facility [Line Items]
Debt Issuance Costs, Gross							$ 15,600,000
London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)	9.00%
London Interbank Offered Rate (LIBOR) [Member] | Interest Rate Floor [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)	1.00%
Base Rate [Member]
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)	8.00%
7.00% Senior Notes Due 2019 [Member]
Line of Credit Facility [Line Items]
Senior notes interest rate (percent)			7.00%		7.00%			7.00%
9.875% Senior Notes Due 2019 [Member]
Line of Credit Facility [Line Items]
Senior notes interest rate (percent)			9.875%		9.875%			9.875%
8.00% Senior Secured Notes due 2019 [Member]
Line of Credit Facility [Line Items]
Senior notes interest rate (percent)			8.00%		8.00%			8.00%
7.25% Senior Notes Due 2020 [Member]
Line of Credit Facility [Line Items]
Senior notes interest rate (percent)			7.25%		7.25%			7.25%
7.25% Senior Notes Due 2021 [Member]
Line of Credit Facility [Line Items]
Senior notes interest rate (percent)			7.25%		7.25%			7.25%

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Valuation Allowance [Line Items]
Benefit from income taxes	$ (245)	$ (4,071)	$ (1,356)	$ (7,467)
Valuation Allowance, Operating Loss Carryforwards [Member] | Domestic Tax Authority [Member]
Valuation Allowance [Line Items]
Valuation allowance	151,000		151,000
Change in amount of valuation allowance				104,600
Valuation Allowance, Operating Loss Carryforwards [Member] | State and Local Jurisdiction [Member]
Valuation Allowance [Line Items]
Valuation allowance	$ 7,000		$ 7,000
Change in amount of valuation allowance				$ 5,800

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of senior notes and other long-term debt, including amounts classified as current	$ 928.5	$ 928.5	$ 937.1
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net unrealized gains (losses) related to level 3 financial instruments	$ 1.4	$ 1

Fair Value Measurements (Summar

Fair Value Measurements (Summary Of Financial Assets And Liabilities Accounted For At Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Assets:
Investments in marketable securities	$ 205,646	$ 201,910
Derivatives	8,680	$ 9,052
Total assets	214,326
Liabilities:
Derivatives	476
Level 1 [Member]
Assets:
Investments in marketable securities	49,742
Derivatives	2,893
Total assets	52,635
Liabilities:
Derivatives	437
Level 2 [Member]
Assets:
Investments in marketable securities	155,904
Derivatives	977
Total assets	156,881
Liabilities:
Derivatives	0
Level 3 [Member]
Assets:
Investments in marketable securities	0
Derivatives	4,810
Total assets	4,810
Liabilities:
Derivatives	$ 39

Fair Value Measurements (Summ61

Fair Value Measurements (Summary Of Change In The Fair Values Of Financial Instruments Categorized As Level 3) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2016
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 2,702	$ 2,432
Realized and unrealized gains recognized in earnings, net	1,061	202
Realized and unrealized gains recognized in other comprehensive income, net	0	0
Purchases	2,073	3,435
Issuances	(255)	(488)
Settlements	(810)	(810)
Ending balance	$ 4,771	$ 4,771

Employee Benefit Plans (Pension

Employee Benefit Plans (Pension And Other Postretirement Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 1	$ 0	$ 5
Interest cost	3,197	3,695	6,535	7,265
Expected return on plan assets	(4,444)	(4,466)	(8,982)	(10,231)
Curtailments	454	0	454	0
Amortization of other actuarial losses (gains)	924	3,185	1,681	5,243
Net benefit cost (credit)	131	2,415	(312)	2,282
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	105	200	265	433
Interest cost	1,138	308	2,272	643
Curtailments	(970)	0	(970)	0
Amortization of prior service credits	(2,672)	(2,083)	(5,345)	(4,167)
Amortization of other actuarial losses (gains)	(566)	(599)	(1,132)	(1,055)
Net benefit cost (credit)	$ (2,965)	$ (2,174)	$ (4,910)	$ (4,146)

Commitments and Contingencies (

Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Amount accrued	$ 2.8	$ 2.8

Segment Information (Schedule O

Segment Information (Schedule Of Operating Segment Results) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting Information [Line Items]
Revenues	$ 420,298	$ 644,462	$ 848,404	$ 1,321,467
Adjusted EBITDA	(8,360)	45,328	(18,386)	127,100
Depreciation, depletion and amortization	58,459	97,372	122,158	202,246
Amortization of acquired sales contracts, net	1	(1,644)	(832)	(5,034)
Capital expenditures	68,211	76,481	74,137	99,361
Operating Segments [Member] | PRB [Member]
Segment Reporting Information [Line Items]
Revenues	207,735	342,480	430,857	733,686
Adjusted EBITDA	15,932	56,654	22,942	128,716
Depreciation, depletion and amortization	30,145	42,711	62,905	87,072
Amortization of acquired sales contracts, net	76	(761)	30	(2,046)
Capital expenditures	489	4,425	499	21,394
Operating Segments [Member] | APP [Member]
Segment Reporting Information [Line Items]
Revenues	170,940	224,298	344,558	447,737
Adjusted EBITDA	(5,963)	11,427	1,645	51,234
Depreciation, depletion and amortization	19,422	42,203	41,751	90,930
Amortization of acquired sales contracts, net	(75)	(883)	(862)	(2,988)
Capital expenditures	6,740	7,948	10,369	11,333
Operating Segments [Member] | Other Segments [Member]
Segment Reporting Information [Line Items]
Revenues	41,623	77,684	72,989	140,044
Adjusted EBITDA	595	7,456	(2,732)	9,147
Depreciation, depletion and amortization	8,110	10,834	16,043	20,889
Amortization of acquired sales contracts, net	0	0	0	0
Capital expenditures	949	1,668	2,910	4,310
Intersegment Eliminations [Member] | Corporate, Other and Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0
Adjusted EBITDA	(18,924)	(30,209)	(40,241)	(61,997)
Depreciation, depletion and amortization	782	1,624	1,459	3,355
Amortization of acquired sales contracts, net	0	0	0	0
Capital expenditures	$ 60,033	$ 62,440	$ 60,359	$ 62,324

Segment Information (Reconcilia

Segment Information (Reconciliation Statement Of Segment Income from Operations To Consolidated Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting [Abstract]
Adjusted EBITDA	$ (8,360)		$ 45,328	$ (18,386)	$ 127,100
Depreciation, depletion and amortization	(58,459)		(97,372)	(122,158)	(202,246)
Amortization of acquired sales contracts, net	(1)		1,644	832	5,034
Asset impairment and mine closure costs	(43,701)	$ (85,500)	(19,146)	(129,221)	(19,146)
Interest expense, net	(44,340)		(98,612)	(87,653)	(195,491)
Nonoperating expenses	(21,271)		(4,016)	(27,359)	(4,016)
Loss before income taxes	$ (176,132)		$ (172,174)	$ (383,945)	$ (288,765)

Subsequent Events (Narrative) (

Subsequent Events (Narrative) (Details)	Jul. 06, 2016USD ($)	Jun. 30, 2016USD ($)	Jul. 20, 2016	Jul. 05, 2016director
Subsequent Event [Line Items]
Plan of Reorganization, Terms of Plan, Unsecured Note Holders, Cash Distribution to Senior Lenders		$ 115,000,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Unsecured note holders percentage of common stock outstanding upon reorganization (percent)	6.00%
Warrant exercise period	7 years
Unsecured note holders election to receive percentage of common stock outstanding upon reorganization (percent)	12.00%
Unsecured note holders election to receive common stock with a total equity value	$ 1,425,000,000
Unsecured note holders election to receive a pro rata amount of cash	25,000,000
Unsecured note holders right to receive their pro rata amount of cash to settle claim	22,636,000
Plan of Reorganization, Terms of Plan, Other General Holders, Pro Rata Amount of Cash to Settle Claim	7,364,000
Plan of Reorganization, Terms of Plan, Unsecured Note Holders, Cash Distribution to Senior Lenders	$ 145,000,000
Other general holders reduction in percentage of common stock outstanding upon reorganization (percent)	6.00%
Senior management's waiver to receive incentive compensation	$ 6,000,000
Number of directors | director				7
Unused commitment fee (percent)			5.00%
Subsequent Event [Member] | Director [Member]
Subsequent Event [Line Items]
Number of directors | director				6
Subsequent Event [Member] | GSO Capital [Member]
Subsequent Event [Line Items]
Amount paid to settle claim	$ 5,000,000

Supplemental Consolidating Fi67

Supplemental Consolidating Financial Information (Schedule Of Condensed Consolidating Statements Of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 420,298		$ 644,462	$ 848,404	$ 1,321,467
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	419,042		566,252	838,358	1,128,574
Depreciation, depletion and amortization	58,459		97,372	122,158	202,246
Amortization of acquired sales contracts, net	1		(1,644)	(832)	(5,034)
Change in fair value of coal derivatives and coal trading activities, net	1,158		1,211	2,368	2,431
Asset impairment and mine closure costs	43,701	$ 85,500	19,146	129,221	19,146
Selling, general and administrative expenses	19,019		24,268	38,845	46,873
Other operating (income) expense, net	(10,561)		7,403	(12,781)	16,489
Total operating expenses	530,819		714,008	1,117,337	1,410,725
Loss from investment in subsidiaries	0		0	0	0
Loss from operations	(110,521)		(69,546)	(268,933)	(89,258)
Interest expense, net
Interest expense (contractual interest of $100,767 and $199,332 for the three and six months ended June 30, 2016)	(45,273)		(99,574)	(89,724)	(198,826)
Interest and investment income	933		962	2,071	3,335
Interest expense, net	(44,340)		(98,612)	(87,653)	(195,491)
Nonoperating expense
Expenses related to proposed debt restructuring	0		(4,016)	(2,213)	(4,016)
Reorganization items, net	(21,271)		0	(25,146)	0
Nonoperating income (expense)	(21,271)		(4,016)	(27,359)	(4,016)
Loss before income taxes	(176,132)		(172,174)	(383,945)	(288,765)
Benefit from income taxes	(245)		(4,071)	(1,356)	(7,467)
Net loss	(175,887)		(168,103)	(382,589)	(281,298)
Total comprehensive income (loss)	(178,294)		(167,887)	(384,136)	(277,478)
Contractual interest	100,767			199,332
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0		0	0	0
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	(548)		(847)	(1,095)	(1,681)
Depreciation, depletion and amortization	0		0	0	0
Amortization of acquired sales contracts, net	0		0	0	0
Change in fair value of coal derivatives and coal trading activities, net	0		0	0	0
Asset impairment and mine closure costs	0		0	0	0
Selling, general and administrative expenses	(343)		(493)	(710)	(1,019)
Other operating (income) expense, net	891		1,340	1,805	2,700
Total operating expenses	0		0	0	0
Loss from investment in subsidiaries	78,965		30,462	202,953	9,413
Loss from operations	78,965		30,462	202,953	9,413
Interest expense, net
Interest expense (contractual interest of $100,767 and $199,332 for the three and six months ended June 30, 2016)	29,772		27,360	60,155	54,202
Interest and investment income	(29,772)		(27,360)	(60,155)	(54,202)
Interest expense, net	0		0	0	0
Nonoperating expense
Expenses related to proposed debt restructuring	0		0	0	0
Reorganization items, net	0			0
Nonoperating income (expense)	0			0
Loss before income taxes	78,965		30,462	202,953	9,413
Benefit from income taxes	0		0	0	0
Net loss	78,965		30,462	202,953	9,413
Total comprehensive income (loss)	81,818		30,624	206,808	6,335
Parent/Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0		0	0	0
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	3,351		5,908	5,537	13,378
Depreciation, depletion and amortization	738		1,013	1,494	2,073
Amortization of acquired sales contracts, net	0		0	0	0
Change in fair value of coal derivatives and coal trading activities, net	0		0	0	0
Asset impairment and mine closure costs	3,101		1,225	6,330	1,225
Selling, general and administrative expenses	12,959		17,166	26,497	32,605
Other operating (income) expense, net	(3,455)		(138)	(4,552)	3,562
Total operating expenses	16,694		25,174	35,306	52,843
Loss from investment in subsidiaries	(78,965)		(30,462)	(202,953)	(9,413)
Loss from operations	(95,659)		(55,636)	(238,259)	(62,256)
Interest expense, net
Interest expense (contractual interest of $100,767 and $199,332 for the three and six months ended June 30, 2016)	(66,126)		(119,231)	(132,365)	(237,286)
Interest and investment income	6,924		6,675	14,034	14,747
Interest expense, net	(59,202)		(112,556)	(118,331)	(222,539)
Nonoperating expense
Expenses related to proposed debt restructuring	0		(4,016)	(2,213)	(4,016)
Reorganization items, net	(21,271)			(25,146)
Nonoperating income (expense)	(21,271)			(27,359)
Loss before income taxes	(176,132)		(172,208)	(383,949)	(288,811)
Benefit from income taxes	(245)		(4,105)	(1,360)	(7,513)
Net loss	(175,887)		(168,103)	(382,589)	(281,298)
Total comprehensive income (loss)	(178,294)		(167,887)	(384,136)	(277,478)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	420,298		644,462	848,404	1,321,467
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	416,239		561,191	833,916	1,116,877
Depreciation, depletion and amortization	57,721		96,359	120,664	200,171
Amortization of acquired sales contracts, net	1		(1,644)	(832)	(5,034)
Change in fair value of coal derivatives and coal trading activities, net	1,158		1,211	2,368	2,431
Asset impairment and mine closure costs	40,600		17,921	122,891	17,921
Selling, general and administrative expenses	5,268		6,270	10,651	12,514
Other operating (income) expense, net	(7,117)		7,483	(8,268)	12,760
Total operating expenses	513,870		688,791	1,081,390	1,357,640
Loss from investment in subsidiaries	0		0	0	0
Loss from operations	(93,572)		(44,329)	(232,986)	(36,173)
Interest expense, net
Interest expense (contractual interest of $100,767 and $199,332 for the three and six months ended June 30, 2016)	(6,607)		(6,576)	(12,973)	(13,340)
Interest and investment income	22,565		20,256	45,858	40,030
Interest expense, net	15,958		13,680	32,885	26,690
Nonoperating expense
Expenses related to proposed debt restructuring	0			0
Reorganization items, net	0			0
Nonoperating income (expense)	0			0
Loss before income taxes	(77,614)		(30,649)	(200,101)	(9,483)
Benefit from income taxes	0		0	0	0
Net loss	(77,614)		(30,649)	(200,101)	(9,483)
Total comprehensive income (loss)	(80,467)		(30,811)	(203,956)	(6,405)
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0		0	0	0
Costs, expenses and other
Cost of sales (exclusive of items shown separately below)	0		0	0	0
Depreciation, depletion and amortization	0		0	0	2
Amortization of acquired sales contracts, net	0		0	0	0
Change in fair value of coal derivatives and coal trading activities, net	0		0	0	0
Asset impairment and mine closure costs	0		0	0	0
Selling, general and administrative expenses	1,135		1,325	2,407	2,773
Other operating (income) expense, net	(880)		(1,282)	(1,766)	(2,533)
Total operating expenses	255		43	641	242
Loss from investment in subsidiaries	0		0	0	0
Loss from operations	(255)		(43)	(641)	(242)
Interest expense, net
Interest expense (contractual interest of $100,767 and $199,332 for the three and six months ended June 30, 2016)	(2,312)		(1,127)	(4,541)	(2,402)
Interest and investment income	1,216		1,391	2,334	2,760
Interest expense, net	(1,096)		264	(2,207)	358
Nonoperating expense
Expenses related to proposed debt restructuring	0			0
Reorganization items, net	0			0
Nonoperating income (expense)	0			0
Loss before income taxes	(1,351)		221	(2,848)	116
Benefit from income taxes			34	4	46
Net loss	(1,351)		187	(2,852)	70
Total comprehensive income (loss)	$ (1,351)		$ 187	$ (2,852)	$ 70

Supplemental Consolidating Fi68

Supplemental Consolidating Financial Information (Schedule Of Condensed Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents	$ 269,814	$ 450,781	$ 439,655	$ 734,231
Short term investments	203,417	200,192
Restricted cash	102,236	97,542
Receivables	144,464	135,767
Inventories	172,698	196,720
Other	51,569	57,923
Total current assets	944,198	1,138,925
Property, plant and equipment, net	3,493,553	3,619,029
Investment in subsidiaries	0	0
Intercompany receivables	0	0
Note receivable from Arch Western	0	0
Other	247,474	283,927
Total other assets	247,474	283,927
Total assets	4,685,225	5,041,881
Liabilities and Stockholders’ Equity
Accounts payable	78,043	128,131
Accrued expenses and other current liabilities	153,028	329,450
Current maturities of debt	0	5,042,353
Total current liabilities	231,071	5,499,934
Long-term debt	0	30,953
Intercompany payables	0	0
Note payable to Arch Coal	0	0
Asset retirement obligations	390,634	396,659
Accrued pension benefits	19,853	27,373
Accrued postretirement benefits other than pension	87,286	99,810
Accrued workers’ compensation	118,997	112,270
Other noncurrent liabilities	33,918	119,171
Total liabilities not subject to compromise	881,759	6,286,170
Liabilities subject to compromise	5,430,456	0
Total liabilities	6,312,215	6,286,170
Stockholders' equity	(1,626,990)	(1,244,289)
Total liabilities and stockholders’ deficit	4,685,225	5,041,881
Eliminations [Member]
Assets
Cash and cash equivalents	0	0	0	0
Short term investments	0	0
Restricted cash	0	0
Receivables	(4,942)	(4,430)
Inventories	0	0
Other	0	0
Total current assets	(4,942)	(4,430)
Property, plant and equipment, net	428	413
Investment in subsidiaries	(4,648,697)	(4,887,905)
Intercompany receivables	(2,269,237)	(2,253,312)
Note receivable from Arch Western	(675,000)	(675,000)
Other	0	0
Total other assets	(7,592,934)	(7,816,217)
Total assets	(7,597,448)	(7,820,234)
Liabilities and Stockholders’ Equity
Accounts payable	0	0
Accrued expenses and other current liabilities	(4,942)	(4,430)
Current maturities of debt	0	0
Total current liabilities	(4,942)	(4,430)
Long-term debt	0	0
Intercompany payables	(2,269,237)	(2,253,313)
Note payable to Arch Coal	(675,000)	(675,000)
Asset retirement obligations	0	0
Accrued pension benefits	0	0
Accrued postretirement benefits other than pension	0	0
Accrued workers’ compensation	0	0
Other noncurrent liabilities	0	0
Total liabilities not subject to compromise	(2,949,179)
Total liabilities	(2,949,179)	(2,932,743)
Stockholders' equity	(4,648,269)	(4,887,491)
Total liabilities and stockholders’ deficit	(7,597,448)	(7,820,234)
Parent/Issuer [Member]
Assets
Cash and cash equivalents	207,932	337,646	367,668	572,185
Short term investments	203,417	200,192
Restricted cash	0	0
Receivables	11,935	12,463
Inventories	0	0
Other	22,370	18,160
Total current assets	445,654	568,461
Property, plant and equipment, net	6,198	7,747
Investment in subsidiaries	4,648,697	4,887,905
Intercompany receivables	0	0
Note receivable from Arch Western	675,000	675,000
Other	42,945	39,302
Total other assets	5,366,642	5,602,207
Total assets	5,818,494	6,178,415
Liabilities and Stockholders’ Equity
Accounts payable	28,774	8,495
Accrued expenses and other current liabilities	66,771	162,268
Current maturities of debt	0	5,031,603
Total current liabilities	95,545	5,202,366
Long-term debt	0	0
Intercompany payables	2,038,697	2,043,308
Note payable to Arch Coal	0	0
Asset retirement obligations	1,043	1,005
Accrued pension benefits	3,795	12,390
Accrued postretirement benefits other than pension	72,070	79,826
Accrued workers’ compensation	16,887	24,247
Other noncurrent liabilities	11,249	59,976
Total liabilities not subject to compromise	2,239,286
Liabilities subject to compromise	5,206,626
Total liabilities	7,445,912	7,423,118
Stockholders' equity	(1,627,418)	(1,244,703)
Total liabilities and stockholders’ deficit	5,818,494	6,178,415
Guarantor Subsidiaries [Member]
Assets
Cash and cash equivalents	50,426	100,428	60,568	150,358
Short term investments	0	0
Restricted cash	0	0
Receivables	992	3,153
Inventories	172,698	196,720
Other	26,502	38,794
Total current assets	250,618	339,095
Property, plant and equipment, net	3,486,927	3,610,869
Investment in subsidiaries	0	0
Intercompany receivables	2,269,237	2,253,312
Note receivable from Arch Western	0	0
Other	203,399	243,806
Total other assets	2,472,636	2,497,118
Total assets	6,210,181	6,447,082
Liabilities and Stockholders’ Equity
Accounts payable	49,237	119,633
Accrued expenses and other current liabilities	90,356	170,575
Current maturities of debt	0	10,750
Total current liabilities	139,593	300,958
Long-term debt	0	30,953
Intercompany payables	0	0
Note payable to Arch Coal	675,000	675,000
Asset retirement obligations	389,591	395,654
Accrued pension benefits	16,058	14,983
Accrued postretirement benefits other than pension	15,216	19,984
Accrued workers’ compensation	102,110	88,023
Other noncurrent liabilities	22,461	58,847
Total liabilities not subject to compromise	1,360,029
Liabilities subject to compromise	223,830
Total liabilities	1,583,859	1,584,402
Stockholders' equity	4,626,322	4,862,680
Total liabilities and stockholders’ deficit	6,210,181	6,447,082
Non-Guarantor Subsidiaries [Member]
Assets
Cash and cash equivalents	11,456	12,707	$ 11,419	$ 11,688
Short term investments	0	0
Restricted cash	102,236	97,542
Receivables	136,479	124,581
Inventories	0	0
Other	2,697	969
Total current assets	252,868	235,799
Property, plant and equipment, net	0
Investment in subsidiaries	0	0
Intercompany receivables	0	0
Note receivable from Arch Western	0	0
Other	1,130	819
Total other assets	1,130	819
Total assets	253,998	236,618
Liabilities and Stockholders’ Equity
Accounts payable	32	3
Accrued expenses and other current liabilities	843	1,037
Current maturities of debt	0	0
Total current liabilities	875	1,040
Long-term debt	0	0
Intercompany payables	230,540	210,005
Note payable to Arch Coal	0	0
Asset retirement obligations	0	0
Accrued pension benefits	0	0
Accrued postretirement benefits other than pension	0	0
Accrued workers’ compensation	0	0
Other noncurrent liabilities	208	348
Total liabilities not subject to compromise	231,623
Total liabilities	231,623	211,393
Stockholders' equity	22,375	25,225
Total liabilities and stockholders’ deficit	$ 253,998	$ 236,618

Supplemental Consolidating Fi69

Supplemental Consolidating Financial Information (Schedule Of Condensed Consolidating Statements Of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			$ (60,252)	$ (125,575)
Investing Activities
Capital expenditures	$ (68,211)	$ (76,481)	(74,137)	(99,361)
Additions to prepaid royalties			(217)	(409)
Proceeds from (consideration paid for) disposals and divestitures			(3,303)	991
Purchases of marketable securities			(98,750)	(161,336)
Proceeds from sale or maturity of marketable securities and other investments			94,589	157,729
Investments in and advances to affiliates			(2,890)	(5,138)
Withdrawals (deposits) of restricted cash			(4,695)	(37,885)
Cash used in investing activities			(89,403)	(145,409)
Financing Activities
Payments on term loan			0	(9,750)
Net payments on other debt			(10,293)	(9,826)
Expenses related to proposed debt restructuring			(2,213)	(4,016)
Debt financing costs			(18,806)	0
Transactions with affiliates, net			0	0
Cash used in financing activities			(31,312)	(23,592)
Decrease in cash and cash equivalents			(180,967)	(294,576)
Cash and cash equivalents, beginning of period			450,781	734,231
Cash and cash equivalents, end of period	269,814	439,655	269,814	439,655
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			0	0
Investing Activities
Capital expenditures			0	0
Additions to prepaid royalties			0	0
Proceeds from (consideration paid for) disposals and divestitures			0	0
Purchases of marketable securities			0	0
Proceeds from sale or maturity of marketable securities and other investments			0	0
Investments in and advances to affiliates			0	0
Withdrawals (deposits) of restricted cash			0	0
Cash used in investing activities			0	0
Financing Activities
Payments on term loan				0
Net payments on other debt			0	0
Expenses related to proposed debt restructuring			0	0
Debt financing costs			0
Transactions with affiliates, net			0	0
Cash used in financing activities			0	0
Decrease in cash and cash equivalents			0	0
Cash and cash equivalents, beginning of period			0	0
Cash and cash equivalents, end of period	0	0	0	0
Parent/Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			(102,998)	(295,792)
Investing Activities
Capital expenditures			(26)	(815)
Additions to prepaid royalties			0	0
Proceeds from (consideration paid for) disposals and divestitures			0	0
Purchases of marketable securities			(98,750)	(161,336)
Proceeds from sale or maturity of marketable securities and other investments			94,589	157,729
Investments in and advances to affiliates				(788)
Withdrawals (deposits) of restricted cash			0	0
Cash used in investing activities			(4,187)	(5,210)
Financing Activities
Payments on term loan				(9,750)
Net payments on other debt			(4,372)	(5,973)
Expenses related to proposed debt restructuring			(2,213)	(4,016)
Debt financing costs			(15,625)
Transactions with affiliates, net			(319)	116,224
Cash used in financing activities			(22,529)	96,485
Decrease in cash and cash equivalents			(129,714)	(204,517)
Cash and cash equivalents, beginning of period			337,646	572,185
Cash and cash equivalents, end of period	207,932	367,668	207,932	367,668
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			56,656	163,345
Investing Activities
Capital expenditures			(74,111)	(98,546)
Additions to prepaid royalties			(217)	(409)
Proceeds from (consideration paid for) disposals and divestitures			(3,303)	991
Purchases of marketable securities			0	0
Proceeds from sale or maturity of marketable securities and other investments			0	0
Investments in and advances to affiliates			(2,890)	(4,350)
Withdrawals (deposits) of restricted cash			0	0
Cash used in investing activities			(80,521)	(102,314)
Financing Activities
Payments on term loan				0
Net payments on other debt			(5,921)	(3,853)
Expenses related to proposed debt restructuring			0	0
Debt financing costs			0
Transactions with affiliates, net			(20,216)	(146,968)
Cash used in financing activities			(26,137)	(150,821)
Decrease in cash and cash equivalents			(50,002)	(89,790)
Cash and cash equivalents, beginning of period			100,428	150,358
Cash and cash equivalents, end of period	50,426	60,568	50,426	60,568
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash provided by (used in) operating activities			(13,910)	6,872
Investing Activities
Capital expenditures			0	0
Additions to prepaid royalties			0	0
Proceeds from (consideration paid for) disposals and divestitures			0	0
Purchases of marketable securities			0	0
Proceeds from sale or maturity of marketable securities and other investments			0	0
Investments in and advances to affiliates			0	0
Withdrawals (deposits) of restricted cash			(4,695)	(37,885)
Cash used in investing activities			(4,695)	(37,885)
Financing Activities
Payments on term loan				0
Net payments on other debt			0	0
Expenses related to proposed debt restructuring			0	0
Debt financing costs			(3,181)
Transactions with affiliates, net			20,535	30,744
Cash used in financing activities			17,354	30,744
Decrease in cash and cash equivalents			(1,251)	(269)
Cash and cash equivalents, beginning of period			12,707	11,688
Cash and cash equivalents, end of period	$ 11,456	$ 11,419	$ 11,456	$ 11,419