Arch Resources (ARCH) 10-Q 28 Jul 20 2020 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2020	Jul. 24, 2020
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity File Number	1-13105
Entity Registrant Name	Arch Resources, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	43-0921172
Entity Central Index Key	0001037676
Entity Address, Address Line One	One CityPlace Drive
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	St. Louis
Entity Address, State or Province	MO
Entity Address, Postal Zip Code	63141
City Area Code	314
Local Phone Number	994-2700
Title of 12(b) Security	Common stock, $.01 par value
Trading Symbol	ARCH
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business Company	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		15,146,224
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2

Condensed Consolidated Income S

Condensed Consolidated Income Statements - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenues	$ 319,521	$ 570,222	$ 724,753	$ 1,125,405
Costs, expenses and other operating
Cost of sales (exclusive of items shown separately below)	316,348	451,088	691,347	889,559
Depreciation, depletion and amortization	30,167	26,535	61,475	51,873
Accretion on asset retirement obligations	4,986	5,137	9,992	10,274
Change in fair value of coal derivatives and coal trading activities, net	(129)	(8,400)	614	(21,381)
Selling, general and administrative expenses	19,738	25,209	42,483	49,298
Costs related to proposed joint venture with Peabody Energy	7,851	3,018	11,515	3,018
Severance costs related to voluntary separation plan	7,437		13,265
Gain on property insurance recovery related to Mountain Laurel longwall	(14,518)		(23,518)
Other operating income, net	(5,704)	(3,239)	(11,874)	(4,889)
Costs, expenses and other operating	364,807	503,652	793,930	982,056
Income (loss) from operations	(45,286)	66,570	(69,177)	143,349
Interest expense, net
Interest expense	(3,523)	(4,375)	(6,911)	(8,807)
Interest and investment income	1,793	2,088	3,052	4,231
Interest expense, net	(1,730)	(2,287)	(3,859)	(4,576)
Income (loss) before nonoperating expenses	(47,016)	64,283	(73,036)	138,773
Nonoperating (expenses) income
Non-service related pension and postretirement benefit costs	(1,102)	(1,336)	(2,198)	(3,102)
Reorganization items, net		(16)	26	71
Nonoperating (expenses) income	(1,102)	(1,352)	(2,172)	(3,031)
Income (loss) before income taxes	(48,118)	62,931	(75,208)	135,742
Provision for (benefit from) income taxes	1,206	91	(585)	161
Net income (loss)	$ (49,324)	$ 62,840	$ (74,623)	$ 135,581
Net income (loss) per common share
Basic earnings per common share (in dollars per share)	$ (3.26)	$ 3.80	$ (4.93)	$ 7.97
Diluted earnings per common share (in dollars per share)	$ (3.26)	$ 3.53	$ (4.93)	$ 7.45
Weighted average shares outstanding
Basic weighted average shares outstanding (in shares)	15,145	16,543	15,142	17,018
Diluted weighted average shares outstanding (in shares)	15,145	17,781	15,142	18,190
Dividends declared per common share (in dollars per share)		$ 0.45	$ 0.50	$ 0.90
Dal-Tex and Briar Branch Properties
Costs, expenses and other operating
(Gain) loss on divestitures	$ (1,369)	$ 4,304	$ (1,369)	$ 4,304

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net income (loss)	$ (49,324)	$ 62,840	$ (74,623)	$ 135,581
Derivative instruments
Comprehensive income (loss) before tax	363	(2,778)	(2,306)	(61)
Other comprehensive income (loss), derivative instruments, net of tax	363	(2,778)	(2,306)	(61)
Pension, postretirement and other post-employment benefits
Comprehensive income (loss) before tax	(2,336)	2,902	(16,603)	2,902
Other comprehensive income (loss), pension, postretirement and other post-employment benefits, net of tax	(2,336)	2,902	(16,603)	2,902
Available-for-sale securities
Comprehensive income (loss) before tax	533	274	66	651
Other comprehensive income (loss), available-for-sale securities, net of tax	533	274	66	651
Total other comprehensive income (loss)	(1,440)	398	(18,843)	3,492
Total comprehensive income (loss)	$ (50,764)	$ 63,238	$ (93,466)	$ 139,073

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 150,022	$ 153,020
Short term investments	67,237	135,667
Trade accounts receivable (net of $718 allowance at June 30, 2020)	118,835	168,125
Other receivables	2,960	21,143
Inventories	154,690	130,898
Other current assets	70,758	97,894
Total current assets	564,502	706,747
Property, plant and equipment, net	1,066,614	984,509
Other assets
Equity investments	106,125	105,588
Other noncurrent assets	65,148	70,912
Total other assets	171,273	176,500
Total assets	1,802,389	1,867,756
Current Liabilities
Accounts payable	104,464	133,060
Accrued expenses and other current liabilities	143,304	157,167
Current maturities of debt	25,702	20,753
Total current liabilities	273,470	310,980
Long-term debt	323,854	290,066
Asset retirement obligations	238,883	242,432
Accrued pension benefits	13,875	5,476
Accrued postretirement benefits other than pension	86,772	80,567
Accrued workers' compensation	219,095	215,599
Other noncurrent liabilities	98,658	82,100
Total liabilities	1,254,607	1,227,220
Stockholders' equity
Common stock, $0.01 par value, authorized 300,000 shares, issued 25,235 and 25,220 shares at June 30, 2020 and December 31, 2019, respectively	252	252
Paid-in capital	739,156	730,551
Retained earnings	648,909	731,425
Treasury stock, 10,088 shares at June 30, 2020 and December 31, 2019, respectively, at cost	(827,381)	(827,381)
Accumulated other comprehensive income (loss)	(13,154)	5,689
Total stockholders' equity	547,782	640,536
Total liabilities and stockholders' equity	$ 1,802,389	$ 1,867,756

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Trade accounts receivable, allowance	$ 718
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares issued (in shares)	25,235,000	25,220,000
Treasury stock, shares (in shares)	10,088,000	10,088,000

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Operating activities
Net income (loss)	$ (74,623)	$ 135,581
Adjustments to reconcile to cash from operating activities:
Depreciation, depletion and amortization	61,475	51,873
Accretion on asset retirement obligations	9,992	10,274
Deferred income taxes	13,880	13,385
Employee stock-based compensation expense	8,936	11,473
Gains on disposals and divestitures, net	(3,180)	(1,415)
Amortization relating to financing activities	1,946	1,826
Gain on property insurance recovery related to Mountain Laurel longwall	(23,518)
Changes in:
Receivables	55,817	17,871
Inventories	(23,792)	(47,370)
Accounts payable, accrued expenses and other current liabilities	(42,889)	4,497
Income taxes, net	22,918	24,575
Other	18,960	3,336
Cash provided by operating activities	25,922	225,906
Investing activities
Capital expenditures	(148,561)	(87,854)
Minimum royalty payments	(1,124)	(1,125)
Proceeds from disposals and divestitures	562	1,591
Purchases of short term investments	(17,707)	(89,454)
Proceeds from sales of short term investments	86,079	90,424
Investments in and advances to affiliates, net	(1,059)	(3,275)
Proceeds from property insurance recovery related to Mountain Laurel longwall	23,518
Cash used in investing activities	(58,292)	(89,693)
Financing activities
Payments on term loan due 2024	(1,500)	(1,500)
Proceeds from equipment financing	53,611
Net payments on other debt	(13,592)	(8,845)
Debt financing costs	(1,171)
Dividends paid	(7,645)	(15,264)
Purchases of treasury stock		(143,142)
Payments for taxes related to net share settlement of equity awards	(331)
Other		30
Cash provided by (used in) financing activities	29,372	(168,721)
Decrease in cash and cash equivalents, including restricted cash	(2,998)	(32,508)
Cash and cash equivalents, including restricted cash, beginning of period	153,020	264,937
Cash and cash equivalents, including restricted cash, end of period	150,022	232,429
Cash and cash equivalents, including restricted cash, end of period
Cash and cash equivalents, including restricted cash	$ 150,022	$ 232,429

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Common Stock	Paid-in Capital	Retained Earnings	Treasury Stock, at cost	Accumulated Other Comprehensive Income (Loss)	Total
Beginning Balance at Dec. 31, 2018	$ 250	$ 717,492	$ 527,666	$ (583,883)	$ 43,296	$ 704,821
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends on common shares			(8,111)			(8,111)
Total comprehensive income (loss)			72,741		3,094	75,835
Employee stock-based compensation		5,651				5,651
Purchase of common stock under share repurchase program				(78,249)		(78,249)
Ending Balance at Mar. 31, 2019	250	723,143	592,296	(662,132)	46,390	699,947
Beginning Balance at Dec. 31, 2018	250	717,492	527,666	(583,883)	43,296	704,821
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income (loss)						139,073
Ending Balance at Jun. 30, 2019	250	728,996	647,440	(725,524)	46,788	697,950
Beginning Balance at Mar. 31, 2019	250	723,143	592,296	(662,132)	46,390	699,947
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends on common shares			(7,696)			(7,696)
Total comprehensive income (loss)			62,840		398	63,238
Employee stock-based compensation		5,822				5,822
Purchase of common stock under share repurchase program				(63,392)		(63,392)
Warrants exercised		31				31
Ending Balance at Jun. 30, 2019	250	728,996	647,440	(725,524)	46,788	697,950
Beginning Balance at Dec. 31, 2019	252	730,551	731,425	(827,381)	5,689	640,536
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends on common shares			(7,834)			(7,834)
Total comprehensive income (loss)			(25,299)		(17,403)	(42,702)
Employee stock-based compensation		3,962				3,962
Common stock withheld related to net share settlement of equity awards		(198)				(198)
Ending Balance at Mar. 31, 2020	252	734,315	698,292	(827,381)	(11,714)	593,764
Beginning Balance at Dec. 31, 2019	252	730,551	731,425	(827,381)	5,689	640,536
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income (loss)						(93,466)
Ending Balance at Jun. 30, 2020	252	739,156	648,909	(827,381)	(13,154)	547,782
Beginning Balance at Mar. 31, 2020	252	734,315	698,292	(827,381)	(11,714)	593,764
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Total comprehensive income (loss)			(49,324)		(1,440)	(50,764)
Employee stock-based compensation		4,891				4,891
Common stock withheld related to net share settlement of equity awards		(50)				(50)
Dividend Equivalents earned on RSU grants			(59)			(59)
Ending Balance at Jun. 30, 2020	$ 252	$ 739,156	$ 648,909	$ (827,381)	$ (13,154)	$ 547,782

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity (Deficit) (Parenthetical) - $ / shares shares in Thousands	3 Months Ended
	Jun. 30, 2019	Mar. 31, 2019
Statement of Stockholders' Equity [Abstract]
Dividends declared per common share (in dollars per share)	$ 0.45	$ 0.45
Purchase of shares of common stock under share repurchase program (in shares)	697,255	872,317

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2020
Basis of Presentation
Basis of Presentation	1. The accompanying unaudited condensed consolidated financial statements include the accounts of Arch Resources, Inc. (“Arch Resources”) and its subsidiaries (“Arch” or the “Company”). Unless the context indicates otherwise, the terms “Arch” and the “Company” are used interchangeably in this Quarterly Report on Form 10-Q. 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, 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, 2020 are not necessarily indicative of results to be expected for the year ending December 31, 2020. 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, 2019 included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission. Effective May 15, 2020, Arch Coal, Inc. announced that its name changed to Arch Resources, Inc.

Accounting Policies

Accounting Policies	6 Months Ended
	Jun. 30, 2020
Accounting Policies
Accounting Policies	2. Recently Adopted Accounting Guidance In June 2016, the FASB issued ASU 2016-13, “Financial Instruments-Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments,” and also issued subsequent amendments to the initial guidance under ASU 2018-19, ASU 2019-04 and ASU 2019-05. The standard modifies the measurement approach for credit losses on financial instruments, including trade receivables, from an incurred loss method to a current expected credit loss method, otherwise known as “CECL.” The standard requires the measurement of expected credit losses to be based on relevant information, including historical experience, current conditions and a forecast that is supportable. The Company adopted the standard in the first quarter of 2020, with minimal impact to the Company’s financial results. As part of the adoption, the Company reviewed its’ portfolio of available-for-sale debt securities in an unrealized loss position, and assessed whether it intends to sell, or it is more likely than not that it will be required to sell before recovery of its’ amortized cost basis. The Company determined that is currently does not intend to sell these securities before recovery of their amortized cost basis. Additionally, the Company evaluated whether the decline in fair value has resulted from credit losses or other factors by considering the extent to which the fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the Company compares the present value of the cash flows expected to be collected against the amortized cost basis. A credit loss is recorded if the present value of the cash flows is less than the amortized cost basis, limited by the amount that the fair value is less than the amortized cost basis. Upon adoption, the Company did not record an allowance for credit losses on its available-for-sale debt securities. Additionally, the Company reviewed its open trade receivables arising from contractual coal sales. As part of its analysis, the Company performs periodic credit reviews of all active customers, reviews all trade receivables greater than 90 days past due, calculates historical loss rates and reviews current payment trends of all customers. ​ Recent Accounting Guidance Issued Not Yet Effective In December 2019, the FASB issued ASU 2019- 12, “Income Taxes (Topic 740) Simplifying the Accounting for Income Taxes.” ASU 2019- 12 eliminates certain exceptions related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. The ASU is effective for public companies for fiscal years beginning after December 15, 2020, and interim periods therein with early adoption permitted. The Company is reviewing the provisions of the standard but does not expect a significant impact to the Company's financial statements. In March 2020, the FASB issued ASU 2020-04, "Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting." The amendments provide optional guidance for a limited time to ease the potential burden in accounting for reference rate reform. The new guidance provides optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The amendments apply only to contracts and hedging relationships that reference LIBOR or another reference rate expected to be discontinued due to reference rate reform. These amendments are effective immediately and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022. We are currently evaluating our contracts and the optional expedients provided by the new standard.

Joint Venture with Peabody Ener

Joint Venture with Peabody Energy	6 Months Ended
	Jun. 30, 2020
Joint Venture with Peabody Energy
Joint Venture with Peabody Energy	3. On June 18, 2019, Arch Coal, Inc. (now Arch Resources) entered into a definitive implementation agreement (the “Implementation Agreement”) with Peabody Energy Corporation (“Peabody”), to establish a joint venture that will combine the respective Powder River Basin and Colorado mining operations of Arch Resources and Peabody. Pursuant to the terms of the Implementation Agreement, Arch Resources will hold a 33.5% economic interest, and Peabody will hold a 66.5% economic interest in the joint venture. At the closing of the joint venture transaction, certain of the respective subsidiaries of Arch Resources and Peabody will enter into an Amended and Restated Limited Liability Company Agreement (the “LLC Agreement”). Under the terms of the LLC Agreement, the governance of the joint venture will be overseen by the joint venture’s board of managers, which will initially be comprised of three representatives appointed by Peabody and two representatives appointed by Arch. Decisions of the board of managers will be determined by a majority vote subject to certain specified matters set forth in the LLC Agreement that will require a supermajority vote. Peabody, or one of its affiliates, will initially be appointed as the operator of the joint venture and will manage the day-to-day operations of the joint venture, subject to the supervision of the joint venture’s board of managers. Formation of the joint venture is subject to customary closing conditions, including the termination or expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, the receipt of certain other required regulatory approvals and the absence of injunctions or other legal restraints preventing the formation of the joint venture. Formation of the joint venture does not require approval of the respective stockholders of either Arch or Peabody. On February 26, 2020, the Federal Trade Commission (“FTC”) filed an administrative complaint challenging the proposed joint venture alleging the transaction will eliminate competition between Arch Resources and Peabody, the two major competitors in the market for thermal coal in the Southern Powder River Basin and the two largest coal-mining companies in the United States. The FTC filed a temporary restraining order and preliminary injunction in the U.S. District Court for the Eastern District of Missouri, to maintain the status quo pending an administrative trial on the merits. Between July 14 and July 23, 2020, the federal court in St. Louis conducted an evidentiary hearing, during which both sides further presented their evidence and arguments. Closing arguments are scheduled to take place on August 10, 2020 and a ruling on the FTC’s motion for preliminary injunction is expected by the end of the third quarter 2020. The Company has incurred expenses of $7.9 million and $11.5 million for the three and six months ended June 30, 2020, respectively, associated with the regulatory approval process related to the joint venture. Costs of million were incurred for both the three and six months ended June 30, 2019.

Gain on Property Insurance Reco

Gain on Property Insurance Recovery Related to Mountain Laurel Longwall	6 Months Ended
	Jun. 30, 2020
Gain on Property Insurance Recovery Related to Mountain Laurel Longwall
Gain on Property Insurance Recovery Related to Mountain Laurel Longwall	4. Gain on Property Insurance Recovery Related to Mountain Laurel Longwall The Company recorded a $14.5 million and $23.5 million gain related to a property insurance recovery on the longwall shields at its Mountain Laurel operation during the three and six months ended June 30, 2020, respectively. As a result of geologic conditions in the final longwall panel, Mountain Laurel was unable to recover 123 of the longwall system’s 176 hydraulic shields. All of the cash associated with the insurance recovery was received by the end of the quarter.

Severance Costs Related To Volu

Severance Costs Related To Voluntary Separation Plan	6 Months Ended
	Jun. 30, 2020
Severance Costs Related To Voluntary Separation Plan
Severance Costs Related To Voluntary Separation Plan	5. The Company recorded $7.4 million and $13.3 million of employee severance expense related to a voluntary separation plan during the three and six months ended June 30, 2020, respectively. During the first and second quarters of 2020,

Divestitures

Divestitures	6 Months Ended
	Jun. 30, 2020
Divestitures
Divestitures	6. Divestitures During the quarter, various Dal-Tex and Briar Branch properties in West Virginia were sold to Condor Holdings, LLC. No consideration was received for the sale and a gain of $1.4 million was recorded representing the net liabilities sold. On September 14, 2017, the Company sold Lone Mountain Processing, LLC and two idled mining companies, Cumberland River Coal LLC and Powell Mountain Energy LLC to Revelation Energy LLC, and recorded a gain on the transaction in that year of $21.3 million. Under the terms of the purchase agreement, Revelation assumed certain traumatic workers compensation claims and pneumoconiosis (occupational disease) benefits. On July 1, 2019, Blackjewel LLC and four affiliates, including Revelation Energy LLC filed for Chapter 11 bankruptcy. As a result of the bankruptcy, the Company recorded a $4.3 million charge for these claims as of June 30, 2019.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	6 Months Ended
	Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss)	​ ​ 7. The following items are included in accumulated other comprehensive income (loss) (“AOCI”), net of tax: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension, ​ ​ ​ ​ ​ ​ ​ ​ ​ Postretirement ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ and Other Post- ​ ​ ​ ​ Other ​ ​ Derivative ​ Employment ​ Available-for- ​ Comprehensive ​ ​ Instruments ​ Benefits ​ Sale Securities ​ Income (loss) ​ (In thousands) Balance at December 31, 2019 ​ $ (2,564) ​ $ 8,273 ​ $ (20) $ 5,689 Unrealized losses ​ (2,974) ​ (15,953) ​ 206 (18,721) Amounts reclassified from AOCI ​ 668 ​ (650) ​ (140) (122) Balance at June 30, 2020 ​ $ (4,870) ​ $ (8,330) ​ $ 46 $ (13,154) ​ The following amounts were reclassified out of AOCI: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, Line Item in the Details About AOCI Components 2020 2019 2020 2019 Statement of Operations ​ ​ (In thousands) ​ ​ ​ Coal hedges ​ $ 196 ​ $ 1,743 ​ $ 196 ​ $ 2,104 ​ Revenues Interest rate hedges ​ (648) ​ 514 ​ (864) ​ 1,029 ​ Interest expense ​ ​ — ​ — ​ — ​ — ​ Provision for (benefit from) income taxes ​ ​ $ (452) ​ $ 2,257 ​ $ (668) ​ $ 3,133 ​ Net of tax ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension, postretirement and other post-employment benefits ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of actuarial gains (losses), net ​ $ 232 ​ $ — ​ $ 466 ​ $ — ​ Non-service related pension and postretirement benefit (costs) credits Amortization of prior service credits ​ ​ 27 ​ ​ — ​ ​ 54 ​ ​ — ​ ​ Non-service related pension and postretirement benefit (costs) credits Pension settlement ​ ​ 134 ​ 429 ​ ​ 130 ​ 429 ​ Non-service related pension and postretirement benefit (costs) credits ​ ​ — ​ — ​ — ​ — ​ Provision for (benefit from) income taxes ​ ​ $ 393 ​ $ 429 ​ $ 650 ​ $ 429 ​ Net of tax ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale securities ​ $ 141 ​ $ 15 ​ $ 140 ​ $ 15 ​ Interest and investment income ​ ​ — ​ — ​ — ​ — ​ Provision for (benefit from) income taxes ​ ​ $ 141 ​ $ 15 ​ $ 140 ​ $ 15 ​ Net of tax ​

Inventories

Inventories	6 Months Ended
	Jun. 30, 2020
Inventories
Inventories	8. Inventories consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 31, ​ 2020 2019 ​ ​ (In thousands) Coal ​ $ 67,702 ​ $ 46,815 Repair parts and supplies ​ 86,988 ​ 84,083 ​ ​ $ 154,690 ​ $ 130,898 ​ The repair parts and supplies are stated net of an allowance for slow-moving and obsolete inventories of $2.4 million at June 30, 2020 and $2.2 million at December 31, 2019.

Investments in Available-for-Sa

Investments in Available-for-Sale Securities	6 Months Ended
	Jun. 30, 2020
Investments in Available-for-Sale Securities
Investments in Available-for-Sale Securities	9. The Company has invested in marketable debt securities, primarily highly liquid U.S. Treasury securities and investment grade corporate bonds. These investments are held in the custody of a major financial institution. These securities are classified as available-for-sale securities and, accordingly, the unrealized gains and losses are recorded through other comprehensive income. The Company’s investments in available-for-sale marketable securities are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Allowance ​ ​ ​ ​ ​ ​ ​ ​ Unrealized ​ ​ for Credit ​ Fair ​ Cost Basis Gains Losses ​ ​ Losses Value ​ ​ (In thousands) Available-for-sale: ​ ​ ​ ​ ​ ​ ​ U.S. government and agency securities ​ $ 14,030 ​ $ 24 ​ $ — ​ $ — ​ $ 14,054 Corporate notes and bonds ​ 53,161 ​ 166 ​ (144) ​ — ​ 53,183 Total Investments ​ $ 67,191 ​ $ 190 ​ $ (144) ​ $ — ​ $ 67,237 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Allowance ​ ​ ​ ​ ​ ​ ​ ​ Unrealized ​ ​ for Credit ​ Fair ​ Cost Basis Gains ​ Losses ​ ​ Losses Value ​ (In thousands) Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government and agency securities ​ $ 35,044 ​ $ 1 ​ $ (16) ​ $ — ​ $ 35,029 Corporate notes and bonds ​ 100,643 ​ 200 ​ (205) ​ — ​ 100,638 Total Investments ​ $ 135,687 ​ $ 201 ​ $ (221) ​ $ — ​ $ 135,667 ​ The aggregate fair value of investments with unrealized losses that were owned for less than a year was $12.5 million and $72.3 million at June 30, 2020 and December 31, 2019, respectively. The aggregate fair value of investments with unrealized losses that were owned for over a year was $5.1 million and $0.0 million at June 30, 2020 and December 31, 2019, respectively. The unrealized losses in the Company’s portfolio at June 30, 2020 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, 2020 have maturity dates ranging from the third quarter of 2020 through the third quarter of 2021. 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, 2020
Derivatives
Derivatives	10. Interest rate risk management The Company has entered into interest rate swaps to reduce the variability of cash outflows associated with interest payments on its variable rate term loan. These swaps have been designated as cash flow hedges. For additional information on these arrangements, see Note 12, “Debt and Financing Arrangements,” in the Condensed Consolidated Financial Statements. Diesel fuel price risk management The Company is exposed to price risk with respect to diesel fuel purchased for use in its operations. The Company anticipates purchasing approximately 30 to 35 million gallons of diesel fuel for use in its operations annually. 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, purchased heating oil call options and New York Mercantile Exchange (“NYMEX”) gulf coast diesel swaps and options. At June 30, 2020, the Company had protected the price on the majority of its expected diesel fuel purchases for the remainder of 2020 with approximately 6 million gallons of heating oil call options with an average strike price of $1.74 per gallon and 4 million gallons of NYMEX gulf coast diesel swaps at an average price of approximately $1.03 per gallon. These positions are not designated as hedges for accounting purposes, and therefore, changes in the fair value are recorded immediately to earnings. Coal 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, index-priced 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, 2020, the Company held derivatives for risk management purposes that are expected to settle in the following years: ​ ​ ​ ​ ​ ​ ​ ​ (Tons in thousands) 2020 2021 Total Coal sales 542 — 542 Coal purchases 377 — 377 ​ The Company has also entered into a minimal 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 designated 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 $0.3 million of losses during the remainder of 2020 and $0.3 million of gains during 2021. 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, 2020 ​ ​ ​ December 31, 2019 ​ ​ Fair Value of Derivatives Asset ​ Liability ​ ​ ​ ​ Asset ​ Liability ​ ​ (In thousands) ​ Derivative ​ Derivative ​ ​ ​ ​ Derivative ​ Derivative ​ ​ ​ Derivatives Designated as Hedging Instruments ​ ​ ​ ​ ​ ​ Coal ​ $ 1,047 ​ $ (851) ​ ​ $ 1,351 ​ $ (962) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives Not Designated as Hedging Instruments ​ ​ ​ ​ ​ ​ Heating oil -- diesel purchases ​ 528 ​ — ​ ​ 133 ​ (112) ​ Coal -- held for trading purposes ​ 12,910 ​ (12,870) ​ ​ 18,467 ​ (18,940) ​ Coal -- risk management ​ 11,554 ​ (6,659) ​ ​ 11,662 ​ (5,856) ​ Natural gas ​ — ​ — ​ ​ 3 ​ — ​ Total ​ $ 24,992 ​ $ (19,529) ​ ​ $ 30,265 ​ $ (24,908) ​ Total derivatives ​ $ 26,039 ​ $ (20,380) ​ ​ $ 31,616 ​ $ (25,870) ​ Effect of counterparty netting ​ (20,380) ​ 20,380 ​ ​ (25,759) ​ 25,759 ​ Net derivatives as classified in the balance sheets ​ $ 5,659 ​ $ — ​ $ 5,659 ​ $ 5,857 ​ $ (111) ​ $ 5,746 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 31, ​ ​ ​ ​ 2020 ​ 2019 Net derivatives as reflected on the balance sheets (in thousands) ​ ​ Heating oil and coal Other current assets ​ $ 5,659 ​ $ 5,857 Coal Accrued expenses and other current liabilities ​ — ​ (111) ​ ​ ​ ​ $ 5,659 ​ $ 5,746 ​ The Company had a current liability representing cash collateral owed to a margin account for derivative positions primarily related to coal derivatives of $3.9 million and $4.4 million at June 30, 2020 and December 31, 2019, respectively. These amounts are not included with the derivatives presented in the table above and are included in “accrued expenses and other current liabilities” 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 ​ Gains (Losses) Reclassified from Other Comprehensive Income into Income ​ ​ 2020 ​ 2019 ​ 2020 ​ 2019 Coal sales (1) $ 440 ​ $ 4,010 ​ $ (902) ​ $ 1,743 Coal purchases (2) (439) ​ (340) ​ 706 ​ — Totals ​ $ 1 ​ $ 3,670 ​ $ (196) ​ $ 1,743 ​ Derivatives Not Designated as Hedging Instruments (in thousands) Three Months Ended June 30, ​ ​ ​ ​ ​ ​ ​ ​ ​ Gain (Loss) Recognized ​ ​ ​ 2020 ​ ​ 2019 Coal trading — realized and unrealized (3) $ — ​ $ (718) Coal risk management — unrealized (3) ​ 129 ​ 9,137 Natural gas trading— realized and unrealized (3) ​ — ​ (19) Change in fair value of coal derivatives and coal trading activities, net total $ 129 ​ $ 8,400 ​ ​ ​ ​ ​ ​ ​ Coal risk management— realized (4) $ 2,756 ​ $ (881) Heating oil — diesel purchases (4) $ 328 ​ $ (1,369) 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 ​ Gains (Losses) Reclassified from Other Comprehensive Income into Income ​ ​ 2020 ​ 2019 ​ 2020 ​ 2019 Coal sales (1) $ 599 ​ $ 9,247 ​ $ (902) ​ $ 2,787 Coal purchases (2) (595) ​ (906) ​ 706 ​ (686) Totals ​ $ 4 ​ $ 8,341 ​ $ (196) ​ $ 2,101 ​ Derivatives Not Designated as Hedging Instruments (in thousands) Six Months Ended June 30, Six Months Ended June 30,Six Months Ended June 30,Six Months Ended June 30, ​ ​ ​ ​ ​ ​ ​ ​ Gain (Loss) Recognized ​ 2020 2019 Coal trading— realized and unrealized (3) $ 221 ​ $ (1,101) Coal risk management— unrealized (3) (911) ​ 22,562 Natural gas trading — realized and unrealized (3) 76 ​ (80) Change in fair value of coal derivatives and coal trading activities, net total ​ $ (614) ​ $ 21,381 ​ ​ ​ ​ ​ ​ ​ Coal risk management — realized (4) $ 4,357 ​ $ (5,292) Heating oil — diesel purchases (4) $ (705) ​ $ (732) ​ 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 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 and six month periods ended June 30, 2020 and 2019 Based on fair values at June 30, 2020, 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 gains of approximately $0.2 million.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	6 Months Ended
	Jun. 30, 2020
Accrued Expenses and Other Current Liabilities
Accrued Expenses and Other Current Liabilities	11. Accrued expenses and other current liabilities consist of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 31, ​ ​ 2020 ​ 2019 ​ ​ (In thousands) Payroll and employee benefits ​ $ 46,640 ​ $ 50,929 Taxes other than income taxes ​ 60,465 ​ 69,061 Interest ​ 121 ​ 133 Workers’ compensation ​ 15,004 ​ 16,119 Asset retirement obligations ​ 9,827 ​ 10,366 Other ​ 11,247 ​ 10,559 ​ ​ $ 143,304 ​ $ 157,167 ​

Debt and Financing Arrangements

Debt and Financing Arrangements	6 Months Ended
	Jun. 30, 2020
Debt and Financing Arrangements
Debt and Financing Arrangements	12. ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 31, ​ ​ 2020 ​ 2019 ​ (In thousands) Term loan due 2024 ($290.3 million face value) ​ $ 289,427 ​ $ 290,825 Other ​ 65,085 ​ 25,007 Debt issuance costs ​ (4,956) ​ (5,013) ​ ​ ​ 349,556 ​ ​ 310,819 Less: current maturities of debt ​ 25,702 ​ 20,753 Long-term debt ​ $ 323,854 ​ $ 290,066 ​ Term Loan Facility In 2017, the Company entered into a senior secured term loan credit agreement (the “Credit Agreement”) in an aggregate principal amount of $300 million (the “Term Loan Debt Facility”) with Credit Suisse AG, Cayman Islands Branch, as administrative agent and collateral agent, and the other financial institutions from time to time party thereto (collectively, the “Lenders”). The Term Loan Debt Facility was issued at 99.50% of the face amount and will mature on March 7, 2024. The term loans provided under the Term Loan Debt Facility (the “Term Loans”) are subject to quarterly principal amortization payments in an amount equal to $750,000. During 2018, the Company entered into the Second Amendment (the “Second Amendment”) to its Credit Agreement. The Second Amendment reduced the interest rate on its Term Loan Debt Facility to, at the option of Arch Resources, either (i) the London interbank offered rate (“LIBOR”) plus an applicable margin of 2.75%, subject to a 1.00% LIBOR floor, or (ii) a base rate plus an applicable margin of 1.75%. The LIBOR floor remains at 1.00%. There is no change to the maturities as a result of the Second Amendment. The Term Loan Debt Facility is guaranteed by all existing and future wholly owned domestic subsidiaries of the Company (collectively, the “Subsidiary Guarantors” and, together with Arch Resources, the “Loan Parties”), subject to customary exceptions, and is secured by first priority security interests on substantially all assets of the Loan Parties, including 100% of the voting equity interests of directly owned domestic subsidiaries and 65% of the voting equity interests of directly owned foreign subsidiaries, subject to customary exceptions. The Company has the right to prepay Term Loans at any time, and from time to time, in whole or in part without premium or penalty, upon written notice, except that any prepayment of Term Loans that bear interest at the LIBOR Rate other than at the end of the applicable interest periods therefore shall be made with reimbursement for any funding losses and redeployment costs of the Lenders resulting therefrom. The Term Loan Debt Facility is subject to certain usual and customary mandatory prepayment events, including 100% of net cash proceeds of (i) debt issuances (other than debt permitted to be incurred under the terms of the Term Loan Debt Facility) and (ii) non-ordinary course asset sales or dispositions, subject to customary thresholds, exceptions and reinvestment rights. The Term Loan Debt Facility contains customary affirmative covenants and representations. The Term Loan Debt Facility also contains customary negative covenants, which, among other things, and subject to certain exceptions, include restrictions on (i) indebtedness, (ii) liens, (iii) liquidations, mergers, consolidations and acquisitions, (iv) disposition of assets or subsidiaries, (v) affiliate transactions, (vi) creation or ownership of certain subsidiaries, partnerships and joint ventures, (vii) continuation of or change in business, (viii) restricted payments, (ix) prepayment of subordinated and junior lien indebtedness, (x) restrictions in agreements on dividends, intercompany loans and granting liens on the collateral, (xi) loans and investments, (xii) sale and leaseback transactions, (xiii) changes in organizational documents and fiscal year and (xiv) transactions with respect to bonding subsidiaries. The Term Loan Debt Facility does not contain any financial maintenance covenants. The Term Loan Debt Facility contains customary events of default, subject to customary thresholds and exceptions, including, among other things, (i) nonpayment of principal and nonpayment of interest and fees, (ii) a material inaccuracy of a representation or warranty at the time made, (iii) a failure to comply with any covenant, subject to customary grace periods in the case of certain affirmative covenants, (iv) cross-events of default to indebtedness of at least $50 million, (v) cross-events of default to surety, reclamation or similar bonds securing obligations with an aggregate face amount of at least $50 million, (vi) uninsured judgments in excess of $50 million, (vii) any loan document shall cease to be a legal, valid and binding agreement, (viii) uninsured losses or proceedings against assets with a value in excess of $50 million, (ix) certain ERISA events, (x) a change of control or (xi) bankruptcy or insolvency proceedings relating to the Company or any material subsidiary of the Company. Accounts Receivable Securitization Facility In 2018, the Company extended and amended its existing trade accounts receivable securitization facility provided to Arch Receivable Company, LLC, a special-purpose entity that is a wholly owned subsidiary of Arch Resources (“Arch Receivable”) (the “Extended Securitization Facility”), which supports the issuance of letters of credit and requests for cash advances. The amendment to the Extended Securitization Facility maintained the $160 million borrowing capacity and extended the maturity date to August 27, 2021. Additionally, the amendment provided the Company the opportunity to use credit insurance to increase the pool of eligible receivables for borrowing. Pursuant to the Extended Securitization Facility, Arch Receivable also agreed to a revised schedule of fees payable to the administrator and the providers of the Extended Securitization Facility. The Extended Securitization Facility will terminate at the earliest of (i) August 27, 2021, (ii) if the Liquidity (defined in the Extended Securitization Facility and consistent with the definition in the Inventory Facility) is less than $175 million for a period of 60 consecutive days, the date that is the 364th day after the first day of such 60 consecutive day period, and (iii) the occurrence of certain predefined events substantially consistent with the existing transaction documents. Under the Extended Securitization Facility, Arch Receivable, Arch Resources and certain of Arch Resources’s subsidiaries party to the Extended Securitization Facility have granted to the administrator of the Extended Securitization Facility a first priority security interest in eligible trade accounts receivable generated by such parties from the sale of coal and all proceeds thereof. As of June 30, 2020, letters of credit totaling $15.0 million were outstanding under the facility with $68.2 million available for borrowings. Inventory-Based Revolving Credit Facility In 2017, the Company and certain of its subsidiaries entered into a senior secured inventory-based revolving credit facility in an aggregate principal amount of $40 million (the “Inventory Facility”) with Regions Bank (“Regions”) as administrative agent and collateral agent, as lender and swingline lender (in such capacities, the “Lender”) and as letter of credit issuer. Availability under the Inventory Facility is subject to a borrowing base consisting of (i) 85% of the net orderly liquidation value of eligible coal inventory, (ii) the lesser of (x) 85% of the net orderly liquidation value of eligible parts and supplies inventory and (y) 35% of the amount determined pursuant to clause (i), and (iii) 100% of Arch Resources’s Eligible Cash (defined in the Inventory Facility), subject to reduction for reserves imposed by Regions. In 2018, the Company and certain subsidiaries of Arch Resources amended and extended the Inventory Facility by increasing the facility size by $10 million, bringing the total aggregate amount available to $50 million, subject to borrowing base calculations described above. The commitments under the Inventory Facility will terminate on the date that is the earliest to occur of (i) the date, if any, that is 364 days following the first day that Liquidity (defined in the Inventory Facility and consistent with the definition in the Extended Securitization Facility (as defined below)) is less than $250 million for a period of 60 consecutive days and (ii) the date, if any, that is 60 days following the maturity, termination or repayment in full of the Extended Securitization Facility. Revolving loan borrowings under the Inventory Facility bear interest at a per annum rate equal to, at the option of Arch Resources, either the base rate or the London interbank offered rate plus, in each case, a margin ranging from 2.00% to 2.50% (in the case of LIBOR loans) and 1.00% to 1.50% (in the case of base rate loans) determined using a Liquidity-based grid. Letters of credit under the Inventory Facility are subject to a fee in an amount equal to the applicable margin for LIBOR loans, plus customary fronting and issuance fees. All existing and future direct and indirect domestic subsidiaries of Arch Resources, subject to customary exceptions, will either constitute co-borrowers under or guarantors of the Inventory Facility (collectively with Arch Resources, the “Loan Parties”). The Inventory Facility is secured by first priority security interests in the ABL Priority Collateral (defined in the Inventory Facility) of the Loan Parties and second priority security interests in substantially all other assets of the Loan Parties, subject to customary exceptions (including an exception for the collateral that secures the Extended Securitization Facility). Arch Resources has the right to prepay borrowings under the Inventory Facility at any time and from time to time in whole or in part without premium or penalty, upon written notice, except that any prepayment of such borrowings that bear interest at the LIBOR rate other than at the end of the applicable interest periods therefore shall be made with reimbursement for any funding losses and redeployment costs of the Lender resulting therefrom. The Inventory Facility is subject to certain usual and customary mandatory prepayment events, including non-ordinary course asset sales or dispositions, subject to customary thresholds, exceptions (including exceptions for required prepayments under Arch Resources’s term loan facility) and reinvestment rights. The Inventory Facility contains certain customary affirmative and negative covenants; events of default, subject to customary thresholds and exceptions; and representations, including certain cash management and reporting requirements that are customary for asset-based credit facilities. The Inventory Facility also includes a requirement to maintain Liquidity equal to or exceeding $175 million at all times. As of June 30, 2020, letters of credit totaling $32.4 million were outstanding under the facility with $17.6 million available for borrowings. Equipment Financing On March 4, 2020, the Company entered into an equipment financing arrangement accounted for as debt. The Company received $53.6 million in exchange for conveying an interest in certain equipment in operation at its Leer Mine and entered into a master lease arrangement for that equipment. The financing arrangement contains customary terms and events of default and provides for 48 monthly payments with an average interest rate of 6.34 % maturing on March 4, 2024. Upon maturity, all interests in the subject equipment will revert back to the Company. Interest Rate Swaps The Company has entered into a series of interest rate swaps to fix a portion of the LIBOR interest rate within the term loan. The interest rate swaps qualify for cash flow hedge accounting treatment and as such, the change in the fair value of the interest rate swaps is recorded on the Company’s Condensed Consolidated Balance Sheet as an asset or liability with the effective portion of the gains or losses reported as a component of accumulated other comprehensive income and the ineffective portion reported in earnings. As interest payments are made on the term loan, amounts in accumulated other comprehensive income will be reclassified into earnings through interest expense to reflect a net interest on the term loan equal to the effective yield of the fixed rate of the swap plus 2.75% which is the spread on the revised LIBOR term loan. In the event that an interest rate swap is terminated prior to maturity, gains or losses in accumulated other comprehensive income will remain deferred and be reclassified into earnings in the periods which the hedged forecasted transaction affects earnings. Below is a summary of the Company’s outstanding interest rate swap agreements designated as hedges as of June 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Notional Amount ​ ​ ​ ​ ​ ​ ​ ​ (in millions) Effective Date Fixed Rate Receive Rate Expiration Date ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 200.0 ​ June 30, 2020 2.249 % 1-month LIBOR ​ June 30, 2021 $ 100.0 ​ June 30, 2021 2.315 % 1-month LIBOR ​ June 30, 2023 ​ The fair value of the interest rate swaps at June 30, 2020 is a liability of $5.1 million, which is recorded within Other noncurrent liabilities, with the offset to accumulated other comprehensive income on the Company’s Condensed Consolidated Balance Sheet. The Company realized $0.6 million and $0.9 million of losses during the three and six months ended June 30, 2020, respectively, related to settlements of the interest rate swaps which was recorded to interest expense on the Company’s Condensed Consolidated Statement of Operations. The interest rate swaps are classified as level 2 within the fair value hierarchy.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2020
Income Taxes
Income Taxes	13. A reconciliation of the federal income tax provision at the statutory rate to the actual provision for (benefit from) income taxes follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ ​ 2020 2019 2020 2019 ​ ​ (In thousands) ​ Income tax provision at statutory rate ​ $ (10,105) ​ $ 13,216 ​ $ (15,794) ​ $ 28,506 ​ Percentage depletion allowance ​ (11,768) ​ (3,457) ​ (5,600) ​ (7,764) ​ State taxes, net of effect of federal taxes ​ (1,584) ​ 831 ​ (1,502) ​ 1,843 ​ Change in valuation allowance ​ 19,531 ​ (11,292) ​ 20,381 ​ (23,805) ​ Current expense associated with uncertain tax positions ​ ​ 5,132 ​ ​ 844 ​ ​ 3,101 ​ ​ 1,437 ​ AMT sequestration refund ​ — ​ — ​ (1,171) ​ — ​ Other, net ​ — ​ (51) ​ — ​ (56) ​ Provision for (benefit from) income taxes ​ $ 1,206 ​ $ 91 ​ $ (585) ​ $ 161 ​ ​ During the quarter ended June 30, 2020, the Company received a $37.4 million refund from the Internal Revenue Service consisting of all the remaining refundable alternative minimum tax (AMT) credits and related interest. A FIN48 reserve has been established for ​

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures Measurements
Fair Value Measurements	14. The hierarchy of fair value measurements assigns a level to fair value measurements based on the inputs used in the respective valuation techniques. The levels of the hierarchy, as defined below, give the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. ● Level 1 is defined as observable inputs such as quoted prices in active markets for identical assets. Level 1 assets include U.S. Treasury securities, and coal swaps and futures that are submitted for clearing on the New York Mercantile Exchange. ● Level 2 is defined as observable inputs other than Level 1 prices. These include quoted prices for similar assets or liabilities in an active market, quoted prices for identical assets and liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. The Company’s level 2 assets and liabilities include U.S. government agency securities, coal commodity contracts and interest rate swaps with fair values derived from quoted prices in over-the-counter markets or from prices received from direct broker quotes. ● Level 3 is defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. These include the Company’s commodity option contracts (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, 2020. 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, 2020 ​ Total Level 1 Level 2 Level 3 ​ ​ (In thousands) Assets: ​ ​ ​ ​ Investments in marketable securities ​ $ 67,237 ​ $ 14,054 ​ $ 53,183 ​ $ — Derivatives ​ 5,659 ​ 5,131 ​ 495 ​ 33 Total assets ​ $ 72,896 ​ $ 19,185 ​ $ 53,678 ​ $ 33 Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ Derivatives ​ $ 5,066 ​ $ — ​ $ 5,066 ​ $ — ​ 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 Six Months Ended ​ ​ June 30, 2020 ​ June 30, 2020 ​ ​ (In thousands) Balance, beginning of period $ 89 $ 61 Realized and unrealized losses recognized in earnings, net ​ (56) ​ (1,125) Purchases ​ — ​ 1,235 Issuances ​ — ​ (138) Settlements ​ — ​ — Ending balance ​ $ 33 ​ $ 33 ​ Net unrealized losses of $0.1 million and $0.6 million were recognized in the Condensed Consolidated Statement of Operations within Other operating income, net during the three and six months ended June 30, 2020, respectively, related to Level 3 financial instruments held on June 30, 2020. Fair Value of Long-Term Debt At June 30, 2020 and December 31, 2019, the fair value of the Company’s debt, including amounts classified as current, was $308.9 million and $308.0 million, respectively. Fair values are based upon observed prices in an active market, when available, or from valuation models using market information, which fall into Level 2 in the fair value hierarchy.

Earnings per Common Share

Earnings per Common Share	6 Months Ended
	Jun. 30, 2020
Earnings Per Common Share
Earnings per Common Share	15. The Company computes basic net income (loss) per share using the weighted average number of common shares outstanding during the period. Diluted net income (loss) per share is computed using the weighted average number of common shares and the effect of potentially dilutive securities outstanding during the period. Potentially dilutive securities may consist of warrants, restricted stock units or other contingently issuable shares. The dilutive effect of outstanding warrants, restricted stock units and other contingently issuable shares is reflected in diluted earnings per share by application of the treasury stock method. The weighted average share impact of warrants and restricted stock units that were excluded from the calculation of diluted shares due to the Company incurring a net loss for the three and six month periods ending June 30, 2020 were The following table provides the basis for basic and diluted earnings per share by reconciling the denominators of the computations: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ ​ 2020 2019 2020 2019 ​ (In Thousands) ​ ​ ​ Weighted average shares outstanding: Basic weighted average shares outstanding 15,145 16,543 15,142 17,018 Effect of dilutive securities — 1,238 — 1,172 Diluted weighted average shares outstanding 15,145 17,781 15,142 18,190 ​

Workers Compensation Expense

Workers Compensation Expense	6 Months Ended
	Jun. 30, 2020
Workers Compensation Expense
Workers Compensation Expense	16. The Company is liable under the Federal Mine Safety and Health Act of 1969, as subsequently amended, to provide for pneumoconiosis (occupational disease) benefits to eligible employees, former employees and dependents. The Company currently provides for federal claims principally through a self-insurance program. The Company is also liable under various state workers’ compensation statutes for occupational disease benefits. The occupational disease benefit obligation represents the present value of the actuarially computed present and future liabilities for such benefits over the employees’ applicable years of service. In October 2019, the Company filed an application with the Office of Workers’ Compensation Programs (“OWCP”) within the Department of Labor for reauthorization to self-insure federal black lung benefits. In February 2020, the Company received a reply from the OWCP confirming Arch’s status to remain self-insured contingent upon posting additional collateral of of receipt of the letter. The Company is currently appealing the ruling from the OWCP and has received an extension to self-insure during the appeal process. The Company is evaluating alternatives to self-insurance, including the purchase of commercial insurance to cover these claims. In addition, the Company is liable for workers’ compensation benefits for traumatic injuries which are calculated using actuarially-based loss rates, loss development factors and discounted based on a risk free rate. Traumatic workers’ compensation claims are insured with varying retentions/deductibles, or through state-sponsored workers’ compensation programs. Workers’ compensation expense consists of the following components: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ ​ 2020 2019 2020 2019 ​ ​ ​ (In thousands) ​ Self-insured occupational disease benefits: ​ ​ ​ ​ Service cost ​ $ 1,891 ​ $ 1,669 ​ $ 3,782 ​ $ 3,338 ​ Interest cost (1) ​ 1,399 ​ 1,354 ​ 2,798 ​ 2,708 ​ Net amortization (1) ​ 298 ​ — ​ 595 ​ — ​ Total occupational disease ​ $ 3,588 ​ $ 3,023 ​ $ 7,175 ​ $ 6,046 ​ Traumatic injury claims and assessments ​ 2,100 ​ 2,410 ​ 4,282 ​ 4,554 ​ Total workers’ compensation expense ​ $ 5,688 ​ $ 5,433 ​ $ 11,457 ​ $ 10,600 ​ (1) In accordance with the adoption of ASU 2017-07, “Compensation-Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” these costs are recorded within Nonoperating expenses in the Condensed Consolidated Statement of Operations on the line item “Non-service related pension and postretirement benefit costs.” ​

Employee Benefit Plans

Employee Benefit Plans	6 Months Ended
	Jun. 30, 2020
Employee Benefit Plans
Employee Benefit Plans	17. Employee Benefit Plans The following table details the components of pension benefit costs (credits): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ 2020 2019 2020 2019 ​ ​ (In thousands) Interest cost (1) ​ $ 1,483 ​ $ 2,259 ​ $ 3,087 ​ $ 4,517 Expected return on plan assets (1) ​ (2,023) ​ (2,724) ​ (4,311) ​ (5,447) Pension settlement (1) ​ ​ (134) ​ ​ (429) ​ ​ (130) ​ ​ (429) Amortization of prior service costs (credits) (1) ​ (27) ​ — ​ (54) ​ — Net benefit credit ​ $ (701) ​ $ (894) ​ $ (1,408) ​ $ (1,359) ​ The following table details the components of other postretirement benefit costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ 2020 2019 2020 2019 ​ ​ (In thousands) Service cost ​ $ 106 ​ $ 120 ​ $ 212 ​ $ 240 Interest cost (1) ​ 653 ​ 877 ​ 1,306 ​ 1,753 Amortization of other actuarial losses (gains) (1) ​ (529) ​ — ​ (1,059) ​ — Net benefit cost (credit) ​ $ 230 ​ $ 997 ​ $ 459 ​ $ 1,993 (1) In accordance with the adoption of ASU 2017-07, “Compensation-Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” these costs are recorded within Nonoperating expenses in the Condensed Consolidated Statement of Operations on the line item “Non-service related pension and postretirement benefit costs.” (1)

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2020
Commitments and Contingencies
Commitments and Contingencies	18. 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. The ultimate resolution of any such legal matter could result in outcomes that may be materially different from amounts the Company has accrued for such matters. The Company believes it has recorded adequate reserves for these matters.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2020
Segment Information
Segment Information	19. The Company’s reportable business segments are based on two distinct lines of business, metallurgical and thermal, and may include a number of mine complexes. The Company manages its coal sales by market, not by individual mining complex. Geology, coal transportation routes to customers, and regulatory environments also have a significant impact on the Company’s marketing and operations management. Mining operations are evaluated based on Adjusted EBITDA, per-ton cash operating costs (defined as including all mining costs except depreciation, depletion, amortization, accretion on asset retirement obligations, and pass-through transportation expenses), and on other non-financial measures, such as safety and environmental performance. Adjusted EBITDA is not a measure of financial performance in accordance with generally accepted accounting principles, and items excluded from Adjusted EBITDA are significant in understanding and assessing the Company’s financial condition. Therefore, Adjusted EBITDA should not be considered in isolation, nor as an alternative to net income (loss), income (loss) from operations, cash flows from operations or as a measure of our profitability, liquidity or performance under generally accepted accounting principles. The Company uses Adjusted EBITDA to measure the operating performance of its segments and allocate resources to the segments. Furthermore, analogous measures are used by industry analysts and investors to evaluate the Company’s operating performance. Investors should be aware that the Company’s presentation of Adjusted EBITDA may not be comparable to similarly titled measures used by other companies. The Company reports its results of operations primarily through the following reportable segments: Powder River Basin (PRB) segment containing the Company’s primary thermal operations in Wyoming; the Metallurgical (MET) segment, containing the Company’s metallurgical operations in West Virginia, and the Other Thermal segment containing the Company’s supplementary thermal operations in Colorado and Illinois. On December 13, 2019, the Company closed on its definitive agreement to sell Coal-Mac LLC, an operating mine complex within the Company’s Other Thermal coal segment. Coal-Mac is included in the Other Thermal segment results below up to the date of the divestiture. ​ Operating segment results for the three and six months ended June 30, 2020 and 2019, are presented below. The Corporate, Other and Eliminations grouping includes these charges, as well as the change in fair value of coal derivatives and coal trading activities, net; corporate overhead; land management activities; other support functions; and the elimination of intercompany transactions. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Corporate, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ Other and ​ ​ ​ (In thousands) ​ PRB ​ MET ​ Thermal ​ Eliminations ​ Consolidated Three Months Ended June 30, 2020 ​ ​ ​ ​ ​ Revenues ​ $ 133,096 ​ $ 138,951 ​ $ 41,297 $ 6,177 ​ $ 319,521 Adjusted EBITDA ​ (5,362) ​ 20,910 ​ (4,752) ​ (21,528) ​ (10,732) Depreciation, depletion and amortization ​ 5,283 ​ 22,289 ​ 2,333 ​ 262 ​ 30,167 Accretion on asset retirement obligation ​ 3,495 ​ 486 ​ 347 ​ 658 ​ 4,986 Total assets ​ 247,990 ​ 740,451 ​ 108,238 ​ 705,710 ​ 1,802,389 Capital expenditures ​ 1,145 ​ 57,514 ​ 955 ​ 1,258 ​ 60,872 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues ​ $ 210,149 ​ $ 261,245 ​ $ 98,205 ​ $ 623 ​ $ 570,222 Adjusted EBITDA ​ 14,696 ​ 101,936 ​ 10,922 ​ (21,990) ​ 105,564 Depreciation, depletion and amortization ​ 4,880 ​ 17,343 ​ 3,689 ​ 623 ​ 26,535 Accretion on asset retirement obligation ​ 3,135 ​ 531 ​ 603 ​ 868 ​ 5,137 Total assets ​ 236,527 ​ 605,657 ​ 136,899 ​ 910,447 ​ 1,889,530 Capital expenditures ​ 13,209 ​ 31,150 ​ 3,211 ​ 1,138 ​ 48,708 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues ​ $ 311,556 ​ $ 321,605 ​ $ 73,033 $ 18,559 ​ $ 724,753 Adjusted EBITDA ​ (5,944) ​ 63,630 ​ (6,072) ​ (49,431) ​ 2,183 Depreciation, depletion and amortization ​ 10,491 ​ 44,807 ​ 4,670 ​ 1,507 ​ 61,475 Accretion on asset retirement obligation ​ 6,990 ​ 972 ​ 695 ​ 1,335 ​ 9,992 Total assets ​ 247,990 ​ 740,451 ​ 108,238 ​ 705,710 ​ 1,802,389 Capital expenditures ​ 4,242 ​ 136,162 ​ 4,571 ​ 3,586 ​ 148,561 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues ​ $ 422,878 ​ $ 514,507 ​ $ 184,183 ​ $ 3,837 ​ $ 1,125,405 Adjusted EBITDA ​ 35,279 ​ 193,470 ​ 17,041 ​ (32,972) ​ 212,818 Depreciation, depletion and amortization ​ 9,745 ​ 33,725 ​ 7,124 ​ 1,279 ​ 51,873 Accretion on asset retirement obligation ​ 6,271 ​ 1,061 ​ 1,207 ​ 1,735 ​ 10,274 Total assets ​ 236,527 ​ 605,657 ​ 136,899 ​ 910,447 ​ 1,889,530 Capital expenditures ​ 13,623 ​ 62,374 ​ 9,461 ​ 2,396 ​ 87,854 ​ A reconciliation of net income (loss) to adjusted EBITDA follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ (In thousands) ​ 2020 ​ 2019 ​ 2020 ​ 2019 ​ Net income (loss) ​ $ (49,324) ​ $ 62,840 ​ $ (74,623) ​ $ 135,581 ​ Provision for (benefit from) income taxes ​ ​ 1,206 ​ ​ 91 ​ ​ (585) ​ ​ 161 ​ Interest expense, net ​ 1,730 ​ 2,287 ​ 3,859 ​ 4,576 ​ Depreciation, depletion and amortization ​ 30,167 ​ 26,535 ​ 61,475 ​ 51,873 ​ Accretion on asset retirement obligations ​ 4,986 ​ 5,137 ​ 9,992 ​ 10,274 ​ Costs related to proposed joint venture with Peabody Energy ​ 7,851 ​ 3,018 ​ 11,515 ​ 3,018 ​ Severance costs related to voluntary separation plan ​ 7,437 ​ — ​ 13,265 ​ — ​ Gain on property insurance recovery related to Mountain Laurel longwall ​ (14,518) ​ — ​ (23,518) ​ — ​ (Gain) loss on divestitures ​ ​ (1,369) ​ ​ 4,304 ​ ​ (1,369) ​ ​ 4,304 ​ Non-service related pension and postretirement benefit costs ​ 1,102 ​ 1,336 ​ 2,198 ​ 3,102 ​ Reorganization items, net ​ — ​ 16 ​ (26) ​ (71) ​ Adjusted EBITDA ​ $ (10,732) ​ $ 105,564 ​ $ 2,183 ​ $ 212,818 ​ ​

Revenue Recognition

Revenue Recognition	6 Months Ended
	Jun. 30, 2020
Revenue Recognition
Revenue Recognition	20. ASC 606-10-50-5 requires that entities disclose disaggregated revenue information in categories (such as type of good or service, geography, market, type of contract, etc.) that depict how the nature, amount, timing, and uncertainty of revenue and cash flow are affected by economic factors. ASC 606-10-55-89 explains that the extent to which an entity’s revenue is disaggregated depends on the facts and circumstances that pertain to the entity’s contracts with customers and that some entities may need to use more than one type of category to meet the objective for disaggregating revenue. In general, the Company’s business segmentation is aligned according to the nature and economic characteristics of its coal and customer relationships and provides meaningful disaggregation of each segment’s results. The Company has further disaggregated revenue between North America and Seaborne revenues which depicts the pricing and contract differences between the two. North America revenue is characterized by contracts that typically have a term of one year or longer and typically the pricing is fixed; whereas Seaborne revenue generally is derived by spot or short term contracts with pricing determined at the time of shipment or based on a market index. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Corporate, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ Other and ​ ​ ​ ​ ​ PRB ​ MET ​ Thermal ​ Eliminations ​ Consolidated ​ (in thousands) Three Months Ended June 30, 2020 ​ ​ ​ ​ ​ North America revenues ​ $ 133,096 ​ $ 40,137 ​ $ 31,149 ​ $ 6,177 ​ $ 210,559 Seaborne revenues ​ — ​ 98,814 ​ 10,148 ​ — ​ 108,962 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total revenues ​ $ 133,096 ​ $ 138,951 ​ $ 41,297 ​ $ 6,177 ​ $ 319,521 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ North America revenues ​ $ 210,149 ​ $ 54,896 ​ $ 47,885 ​ $ 623 ​ $ 313,553 Seaborne revenues ​ — ​ 206,349 ​ 50,320 ​ — ​ 256,669 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total revenues ​ $ 210,149 ​ $ 261,245 ​ $ 98,205 ​ $ 623 ​ $ 570,222 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ North America revenues ​ $ 311,375 ​ $ 69,860 ​ $ 59,733 ​ $ 18,559 ​ $ 459,527 Seaborne revenues ​ 181 ​ 251,745 ​ 13,300 ​ — ​ 265,226 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total revenues ​ $ 311,556 ​ $ 321,605 ​ $ 73,033 ​ $ 18,559 ​ $ 724,753 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ North America revenues ​ $ 422,878 ​ $ 99,562 ​ $ 94,414 ​ $ 3,837 ​ $ 620,691 Seaborne revenues ​ — ​ 414,945 ​ 89,769 ​ — ​ 504,714 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total revenues ​ $ 422,878 ​ $ 514,507 ​ $ 184,183 ​ $ 3,837 ​ $ 1,125,405 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of June 30, 2020, the Company has outstanding performance obligations for the remainder of 2020 of 36.2 million tons of fixed price contracts and 2.5 million tons of variable price contracts. Additionally, the Company has outstanding performance obligations beyond 2020 of approximately 69.0 million tons of fixed price contracts and 4.5 million tons of variable price contracts. ​

Leases

Leases	6 Months Ended
	Jun. 30, 2020
Leases
Leases	21. The Company has operating and financing leases for mining equipment, office equipment, office space and transloading terminals with remaining lease terms ranging from less than 1 year to approximately 7 years. Some of these leases include both lease and non-lease components which are accounted for as a single lease component as the Company has elected the practical expedient to combine these components for all leases. As most of the leases do not provide an implicit rate, the Company calculated the ROU assets and lease liabilities using its secured incremental borrowing rate at the lease commencement date. Information related to leases was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, ​ ​ ​ 2020 ​ ​ 2019 Operating lease information: ​ (In thousands) Operating lease cost ​ $ 905 ​ ​ ​ $ 917 ​ Operating cash flows from operating leases ​ 885 ​ ​ ​ ​ 871 ​ Weighted average remaining lease term in years ​ 5.38 ​ ​ ​ ​ 5.06 ​ Weighted average discount rate ​ 5.5 % ​ ​ ​ 5.6 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Financing lease information: ​ ​ ​ ​ ​ ​ ​ Financing lease cost ​ $ 393 ​ ​ ​ $ — ​ Operating cash flows from financing leases ​ 303 ​ ​ ​ ​ — ​ Weighted average remaining lease term in years ​ 4.75 ​ ​ ​ ​ — ​ Weighted average discount rate ​ 6.4 % ​ ​ ​ — % ​ Future minimum lease payments under non-cancellable leases as of June 30, 2020 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating ​ ​ Finance Year ​ Leases ​ ​ Leases ​ (In thousands) 2020 ​ $ 1,683 ​ ​ $ 605 2021 ​ 3,367 ​ ​ 1,210 2022 ​ 3,317 ​ ​ 1,210 2023 ​ 3,285 ​ ​ 1,210 2024 ​ 3,200 ​ ​ 1,210 Thereafter ​ 7,798 ​ ​ 2,111 Total minimum lease payments ​ $ 22,650 ​ ​ $ 7,556 Less imputed interest ​ (3,742) ​ ​ (1,273) ​ ​ ​ ​ ​ ​ ​ ​ Total lease liabilities ​ $ 18,908 ​ ​ $ 6,283 ​ ​ ​ ​ ​ ​ ​ ​ As reflected on balance sheet: ​ ​ ​ ​ ​ Accrued expenses and other current liabilities ​ $ 2,382 ​ ​ $ 833 Other noncurrent liabilities ​ 16,526 ​ ​ 5,450 ​ ​ ​ ​ ​ ​ ​ ​ Total lease liability ​ $ 18,908 ​ ​ $ 6,283 ​ At June 30, 2020, the Company had an $18.2 million ROU operating lease asset and a $6.2 million finance lease asset recorded within “ Other noncurrent assets

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2020
Subsequent Events
Subsequent Events	22. On July 2, 2020 the Company issued $53.1 million of bonds in the U.S. tax-exempt market through the West Virginia Economic Development Authority at a fixed interest rate of 5.00%. The bonds are subject to a mandatory tender for purchase by the company on July 1, 2025. In keeping with the requirements of the tax-exempt issuance, proceeds from the offering will be used to fund the construction of the Leer South mine’s preparation plant and other facilities associated with waste management. The Company received approximately $30 million of cash upon closing, reflecting the amount of qualified expenditures already completed, and will receive the remainder over the next several quarters as work continues.

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2020
Basis of Presentation
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, 2020 are not necessarily indicative of results to be expected for the year ending December 31, 2020. 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, 2019 included in the Company’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission. Effective May 15, 2020, Arch Coal, Inc. announced that its name changed to Arch Resources, Inc.
Recently Adopted Accounting Guidance	Recently Adopted Accounting Guidance In June 2016, the FASB issued ASU 2016-13, “Financial Instruments-Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments,” and also issued subsequent amendments to the initial guidance under ASU 2018-19, ASU 2019-04 and ASU 2019-05. The standard modifies the measurement approach for credit losses on financial instruments, including trade receivables, from an incurred loss method to a current expected credit loss method, otherwise known as “CECL.” The standard requires the measurement of expected credit losses to be based on relevant information, including historical experience, current conditions and a forecast that is supportable. The Company adopted the standard in the first quarter of 2020, with minimal impact to the Company’s financial results. As part of the adoption, the Company reviewed its’ portfolio of available-for-sale debt securities in an unrealized loss position, and assessed whether it intends to sell, or it is more likely than not that it will be required to sell before recovery of its’ amortized cost basis. The Company determined that is currently does not intend to sell these securities before recovery of their amortized cost basis. Additionally, the Company evaluated whether the decline in fair value has resulted from credit losses or other factors by considering the extent to which the fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the Company compares the present value of the cash flows expected to be collected against the amortized cost basis. A credit loss is recorded if the present value of the cash flows is less than the amortized cost basis, limited by the amount that the fair value is less than the amortized cost basis. Upon adoption, the Company did not record an allowance for credit losses on its available-for-sale debt securities. Additionally, the Company reviewed its open trade receivables arising from contractual coal sales. As part of its analysis, the Company performs periodic credit reviews of all active customers, reviews all trade receivables greater than 90 days past due, calculates historical loss rates and reviews current payment trends of all customers. ​ Recent Accounting Guidance Issued Not Yet Effective In December 2019, the FASB issued ASU 2019- 12, “Income Taxes (Topic 740) Simplifying the Accounting for Income Taxes.” ASU 2019- 12 eliminates certain exceptions related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. The ASU is effective for public companies for fiscal years beginning after December 15, 2020, and interim periods therein with early adoption permitted. The Company is reviewing the provisions of the standard but does not expect a significant impact to the Company's financial statements. In March 2020, the FASB issued ASU 2020-04, "Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting." The amendments provide optional guidance for a limited time to ease the potential burden in accounting for reference rate reform. The new guidance provides optional expedients and exceptions for applying U.S. GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The amendments apply only to contracts and hedging relationships that reference LIBOR or another reference rate expected to be discontinued due to reference rate reform. These amendments are effective immediately and may be applied prospectively to contract modifications made and hedging relationships entered into or evaluated on or before December 31, 2022. We are currently evaluating our contracts and the optional expedients provided by the new standard.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	6 Months Ended
	Jun. 30, 2020
Accumulated Other Comprehensive Income (Loss)
Schedule of Accumulated Other Comprehensive Income (Loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension, ​ ​ ​ ​ ​ ​ ​ ​ ​ Postretirement ​ ​ ​ ​ Accumulated ​ ​ ​ ​ ​ and Other Post- ​ ​ ​ ​ Other ​ ​ Derivative ​ Employment ​ Available-for- ​ Comprehensive ​ ​ Instruments ​ Benefits ​ Sale Securities ​ Income (loss) ​ (In thousands) Balance at December 31, 2019 ​ $ (2,564) ​ $ 8,273 ​ $ (20) $ 5,689 Unrealized losses ​ (2,974) ​ (15,953) ​ 206 (18,721) Amounts reclassified from AOCI ​ 668 ​ (650) ​ (140) (122) Balance at June 30, 2020 ​ $ (4,870) ​ $ (8,330) ​ $ 46 $ (13,154)
Schedule of Comprehensive Income Reclassifications	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, Line Item in the Details About AOCI Components 2020 2019 2020 2019 Statement of Operations ​ ​ (In thousands) ​ ​ ​ Coal hedges ​ $ 196 ​ $ 1,743 ​ $ 196 ​ $ 2,104 ​ Revenues Interest rate hedges ​ (648) ​ 514 ​ (864) ​ 1,029 ​ Interest expense ​ ​ — ​ — ​ — ​ — ​ Provision for (benefit from) income taxes ​ ​ $ (452) ​ $ 2,257 ​ $ (668) ​ $ 3,133 ​ Net of tax ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Pension, postretirement and other post-employment benefits ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of actuarial gains (losses), net ​ $ 232 ​ $ — ​ $ 466 ​ $ — ​ Non-service related pension and postretirement benefit (costs) credits Amortization of prior service credits ​ ​ 27 ​ ​ — ​ ​ 54 ​ ​ — ​ ​ Non-service related pension and postretirement benefit (costs) credits Pension settlement ​ ​ 134 ​ 429 ​ ​ 130 ​ 429 ​ Non-service related pension and postretirement benefit (costs) credits ​ ​ — ​ — ​ — ​ — ​ Provision for (benefit from) income taxes ​ ​ $ 393 ​ $ 429 ​ $ 650 ​ $ 429 ​ Net of tax ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Available-for-sale securities ​ $ 141 ​ $ 15 ​ $ 140 ​ $ 15 ​ Interest and investment income ​ ​ — ​ — ​ — ​ — ​ Provision for (benefit from) income taxes ​ ​ $ 141 ​ $ 15 ​ $ 140 ​ $ 15 ​ Net of tax

Inventories (Tables)

Inventories (Tables)	6 Months Ended
	Jun. 30, 2020
Inventories
Inventories	​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 31, ​ 2020 2019 ​ ​ (In thousands) Coal ​ $ 67,702 ​ $ 46,815 Repair parts and supplies ​ 86,988 ​ 84,083 ​ ​ $ 154,690 ​ $ 130,898

Investments in Available-for-_2

Investments in Available-for-Sale Securities (Tables)	6 Months Ended
	Jun. 30, 2020
Investments in Available-for-Sale Securities
Available-for-sale Securities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Allowance ​ ​ ​ ​ ​ ​ ​ ​ Unrealized ​ ​ for Credit ​ Fair ​ Cost Basis Gains Losses ​ ​ Losses Value ​ ​ (In thousands) Available-for-sale: ​ ​ ​ ​ ​ ​ ​ U.S. government and agency securities ​ $ 14,030 ​ $ 24 ​ $ — ​ $ — ​ $ 14,054 Corporate notes and bonds ​ 53,161 ​ 166 ​ (144) ​ — ​ 53,183 Total Investments ​ $ 67,191 ​ $ 190 ​ $ (144) ​ $ — ​ $ 67,237 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ ​ Allowance ​ ​ ​ ​ ​ ​ ​ ​ Unrealized ​ ​ for Credit ​ Fair ​ Cost Basis Gains ​ Losses ​ ​ Losses Value ​ (In thousands) Available-for-sale: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ U.S. government and agency securities ​ $ 35,044 ​ $ 1 ​ $ (16) ​ $ — ​ $ 35,029 Corporate notes and bonds ​ 100,643 ​ 200 ​ (205) ​ — ​ 100,638 Total Investments ​ $ 135,687 ​ $ 201 ​ $ (221) ​ $ — ​ $ 135,667

Derivatives (Tables)

Derivatives (Tables)	6 Months Ended
	Jun. 30, 2020
Derivatives
Schedule of Price Risk Derivatives	​ ​ ​ ​ ​ ​ ​ ​ (Tons in thousands) 2020 2021 Total Coal sales 542 — 542 Coal purchases 377 — 377
Disclosure of Fair Value of Derivatives	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2020 ​ ​ ​ December 31, 2019 ​ ​ Fair Value of Derivatives Asset ​ Liability ​ ​ ​ ​ Asset ​ Liability ​ ​ (In thousands) ​ Derivative ​ Derivative ​ ​ ​ ​ Derivative ​ Derivative ​ ​ ​ Derivatives Designated as Hedging Instruments ​ ​ ​ ​ ​ ​ Coal ​ $ 1,047 ​ $ (851) ​ ​ $ 1,351 ​ $ (962) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Derivatives Not Designated as Hedging Instruments ​ ​ ​ ​ ​ ​ Heating oil -- diesel purchases ​ 528 ​ — ​ ​ 133 ​ (112) ​ Coal -- held for trading purposes ​ 12,910 ​ (12,870) ​ ​ 18,467 ​ (18,940) ​ Coal -- risk management ​ 11,554 ​ (6,659) ​ ​ 11,662 ​ (5,856) ​ Natural gas ​ — ​ — ​ ​ 3 ​ — ​ Total ​ $ 24,992 ​ $ (19,529) ​ ​ $ 30,265 ​ $ (24,908) ​ Total derivatives ​ $ 26,039 ​ $ (20,380) ​ ​ $ 31,616 ​ $ (25,870) ​ Effect of counterparty netting ​ (20,380) ​ 20,380 ​ ​ (25,759) ​ 25,759 ​ Net derivatives as classified in the balance sheets ​ $ 5,659 ​ $ — ​ $ 5,659 ​ $ 5,857 ​ $ (111) ​ $ 5,746 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 31, ​ ​ ​ ​ 2020 ​ 2019 Net derivatives as reflected on the balance sheets (in thousands) ​ ​ Heating oil and coal Other current assets ​ $ 5,659 ​ $ 5,857 Coal Accrued expenses and other current liabilities ​ — ​ (111) ​ ​ ​ ​ $ 5,659 ​ $ 5,746
Effects of Derivatives on Measures of Financial Performance	Derivatives used in Cash Flow Hedging Relationships (in thousands) Three Months Ended June 30, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gain (Loss) Recognized in Other Comprehensive Income ​ Gains (Losses) Reclassified from Other Comprehensive Income into Income ​ ​ 2020 ​ 2019 ​ 2020 ​ 2019 Coal sales (1) $ 440 ​ $ 4,010 ​ $ (902) ​ $ 1,743 Coal purchases (2) (439) ​ (340) ​ 706 ​ — Totals ​ $ 1 ​ $ 3,670 ​ $ (196) ​ $ 1,743 ​ Derivatives Not Designated as Hedging Instruments (in thousands) Three Months Ended June 30, ​ ​ ​ ​ ​ ​ ​ ​ ​ Gain (Loss) Recognized ​ ​ ​ 2020 ​ ​ 2019 Coal trading — realized and unrealized (3) $ — ​ $ (718) Coal risk management — unrealized (3) ​ 129 ​ 9,137 Natural gas trading— realized and unrealized (3) ​ — ​ (19) Change in fair value of coal derivatives and coal trading activities, net total $ 129 ​ $ 8,400 ​ ​ ​ ​ ​ ​ ​ Coal risk management— realized (4) $ 2,756 ​ $ (881) Heating oil — diesel purchases (4) $ 328 ​ $ (1,369) 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 ​ Gains (Losses) Reclassified from Other Comprehensive Income into Income ​ ​ 2020 ​ 2019 ​ 2020 ​ 2019 Coal sales (1) $ 599 ​ $ 9,247 ​ $ (902) ​ $ 2,787 Coal purchases (2) (595) ​ (906) ​ 706 ​ (686) Totals ​ $ 4 ​ $ 8,341 ​ $ (196) ​ $ 2,101 ​ Derivatives Not Designated as Hedging Instruments (in thousands) Six Months Ended June 30, Six Months Ended June 30,Six Months Ended June 30,Six Months Ended June 30, ​ ​ ​ ​ ​ ​ ​ ​ Gain (Loss) Recognized ​ 2020 2019 Coal trading— realized and unrealized (3) $ 221 ​ $ (1,101) Coal risk management— unrealized (3) (911) ​ 22,562 Natural gas trading — realized and unrealized (3) 76 ​ (80) Change in fair value of coal derivatives and coal trading activities, net total ​ $ (614) ​ $ 21,381 ​ ​ ​ ​ ​ ​ ​ Coal risk management — realized (4) $ 4,357 ​ $ (5,292) Heating oil — diesel purchases (4) $ (705) ​ $ (732) ​ 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 Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	6 Months Ended
	Jun. 30, 2020
Accrued Expenses and Other Current Liabilities
Schedule of Accrued Expenses and Other Current Liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 31, ​ ​ 2020 ​ 2019 ​ ​ (In thousands) Payroll and employee benefits ​ $ 46,640 ​ $ 50,929 Taxes other than income taxes ​ 60,465 ​ 69,061 Interest ​ 121 ​ 133 Workers’ compensation ​ 15,004 ​ 16,119 Asset retirement obligations ​ 9,827 ​ 10,366 Other ​ 11,247 ​ 10,559 ​ ​ $ 143,304 ​ $ 157,167

Debt and Financing Arrangemen_2

Debt and Financing Arrangements (Tables)	6 Months Ended
	Jun. 30, 2020
Debt and Financing Arrangements
Schedule of Long-term debt	​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 31, ​ ​ 2020 ​ 2019 ​ (In thousands) Term loan due 2024 ($290.3 million face value) ​ $ 289,427 ​ $ 290,825 Other ​ 65,085 ​ 25,007 Debt issuance costs ​ (4,956) ​ (5,013) ​ ​ ​ 349,556 ​ ​ 310,819 Less: current maturities of debt ​ 25,702 ​ 20,753 Long-term debt ​ $ 323,854 ​ $ 290,066
Schedule of Interest Rate Derivatives	Below is a summary of the Company’s outstanding interest rate swap agreements designated as hedges as of June 30, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Notional Amount ​ ​ ​ ​ ​ ​ ​ ​ (in millions) Effective Date Fixed Rate Receive Rate Expiration Date ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ $ 200.0 ​ June 30, 2020 2.249 % 1-month LIBOR ​ June 30, 2021 $ 100.0 ​ June 30, 2021 2.315 % 1-month LIBOR ​ June 30, 2023

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2020
Income Taxes
Schedule of Components of Income Tax Expense (Benefit)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ ​ 2020 2019 2020 2019 ​ ​ (In thousands) ​ Income tax provision at statutory rate ​ $ (10,105) ​ $ 13,216 ​ $ (15,794) ​ $ 28,506 ​ Percentage depletion allowance ​ (11,768) ​ (3,457) ​ (5,600) ​ (7,764) ​ State taxes, net of effect of federal taxes ​ (1,584) ​ 831 ​ (1,502) ​ 1,843 ​ Change in valuation allowance ​ 19,531 ​ (11,292) ​ 20,381 ​ (23,805) ​ Current expense associated with uncertain tax positions ​ ​ 5,132 ​ ​ 844 ​ ​ 3,101 ​ ​ 1,437 ​ AMT sequestration refund ​ — ​ — ​ (1,171) ​ — ​ Other, net ​ — ​ (51) ​ — ​ (56) ​ Provision for (benefit from) income taxes ​ $ 1,206 ​ $ 91 ​ $ (585) ​ $ 161 ​

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures Measurements
Summary of Financial Assets and Liabilities Accounted for at Fair Value	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2020 ​ Total Level 1 Level 2 Level 3 ​ ​ (In thousands) Assets: ​ ​ ​ ​ Investments in marketable securities ​ $ 67,237 ​ $ 14,054 ​ $ 53,183 ​ $ — Derivatives ​ 5,659 ​ 5,131 ​ 495 ​ 33 Total assets ​ $ 72,896 ​ $ 19,185 ​ $ 53,678 ​ $ 33 Liabilities: ​ ​ ​ ​ ​ ​ ​ ​ Derivatives ​ $ 5,066 ​ $ — ​ $ 5,066 ​ $ —
Summary of Change in the Fair Values of Financial Instruments Categorized as Level 3	​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended Six Months Ended ​ ​ June 30, 2020 ​ June 30, 2020 ​ ​ (In thousands) Balance, beginning of period $ 89 $ 61 Realized and unrealized losses recognized in earnings, net ​ (56) ​ (1,125) Purchases ​ — ​ 1,235 Issuances ​ — ​ (138) Settlements ​ — ​ — Ending balance ​ $ 33 ​ $ 33

Earnings per Common Share (Tabl

Earnings per Common Share (Tables)	6 Months Ended
	Jun. 30, 2020
Earnings Per Common Share
Schedule of Weighted Average Number of Shares	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ ​ 2020 2019 2020 2019 ​ (In Thousands) ​ ​ ​ Weighted average shares outstanding: Basic weighted average shares outstanding 15,145 16,543 15,142 17,018 Effect of dilutive securities — 1,238 — 1,172 Diluted weighted average shares outstanding 15,145 17,781 15,142 18,190

Workers Compensation Expense (T

Workers Compensation Expense (Tables)	6 Months Ended
	Jun. 30, 2020
Workers Compensation Expense
Workers' compensation expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ ​ 2020 2019 2020 2019 ​ ​ ​ (In thousands) ​ Self-insured occupational disease benefits: ​ ​ ​ ​ Service cost ​ $ 1,891 ​ $ 1,669 ​ $ 3,782 ​ $ 3,338 ​ Interest cost (1) ​ 1,399 ​ 1,354 ​ 2,798 ​ 2,708 ​ Net amortization (1) ​ 298 ​ — ​ 595 ​ — ​ Total occupational disease ​ $ 3,588 ​ $ 3,023 ​ $ 7,175 ​ $ 6,046 ​ Traumatic injury claims and assessments ​ 2,100 ​ 2,410 ​ 4,282 ​ 4,554 ​ Total workers’ compensation expense ​ $ 5,688 ​ $ 5,433 ​ $ 11,457 ​ $ 10,600 ​ (1) In accordance with the adoption of ASU 2017-07, “Compensation-Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” these costs are recorded within Nonoperating expenses in the Condensed Consolidated Statement of Operations on the line item “Non-service related pension and postretirement benefit costs.”

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	6 Months Ended
	Jun. 30, 2020
Employee Benefit Plans
Schedule of Pension Benefit Costs (Credits)	The following table details the components of pension benefit costs (credits): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ 2020 2019 2020 2019 ​ ​ (In thousands) Interest cost (1) ​ $ 1,483 ​ $ 2,259 ​ $ 3,087 ​ $ 4,517 Expected return on plan assets (1) ​ (2,023) ​ (2,724) ​ (4,311) ​ (5,447) Pension settlement (1) ​ ​ (134) ​ ​ (429) ​ ​ (130) ​ ​ (429) Amortization of prior service costs (credits) (1) ​ (27) ​ — ​ (54) ​ — Net benefit credit ​ $ (701) ​ $ (894) ​ $ (1,408) ​ $ (1,359) ​ The following table details the components of other postretirement benefit costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ 2020 2019 2020 2019 ​ ​ (In thousands) Service cost ​ $ 106 ​ $ 120 ​ $ 212 ​ $ 240 Interest cost (1) ​ 653 ​ 877 ​ 1,306 ​ 1,753 Amortization of other actuarial losses (gains) (1) ​ (529) ​ — ​ (1,059) ​ — Net benefit cost (credit) ​ $ 230 ​ $ 997 ​ $ 459 ​ $ 1,993 (1) In accordance with the adoption of ASU 2017-07, “Compensation-Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost,” these costs are recorded within Nonoperating expenses in the Condensed Consolidated Statement of Operations on the line item “Non-service related pension and postretirement benefit costs.” (1)

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2020
Segment Information
Schedule of Operating Segment Results	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Corporate, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ Other and ​ ​ ​ (In thousands) ​ PRB ​ MET ​ Thermal ​ Eliminations ​ Consolidated Three Months Ended June 30, 2020 ​ ​ ​ ​ ​ Revenues ​ $ 133,096 ​ $ 138,951 ​ $ 41,297 $ 6,177 ​ $ 319,521 Adjusted EBITDA ​ (5,362) ​ 20,910 ​ (4,752) ​ (21,528) ​ (10,732) Depreciation, depletion and amortization ​ 5,283 ​ 22,289 ​ 2,333 ​ 262 ​ 30,167 Accretion on asset retirement obligation ​ 3,495 ​ 486 ​ 347 ​ 658 ​ 4,986 Total assets ​ 247,990 ​ 740,451 ​ 108,238 ​ 705,710 ​ 1,802,389 Capital expenditures ​ 1,145 ​ 57,514 ​ 955 ​ 1,258 ​ 60,872 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues ​ $ 210,149 ​ $ 261,245 ​ $ 98,205 ​ $ 623 ​ $ 570,222 Adjusted EBITDA ​ 14,696 ​ 101,936 ​ 10,922 ​ (21,990) ​ 105,564 Depreciation, depletion and amortization ​ 4,880 ​ 17,343 ​ 3,689 ​ 623 ​ 26,535 Accretion on asset retirement obligation ​ 3,135 ​ 531 ​ 603 ​ 868 ​ 5,137 Total assets ​ 236,527 ​ 605,657 ​ 136,899 ​ 910,447 ​ 1,889,530 Capital expenditures ​ 13,209 ​ 31,150 ​ 3,211 ​ 1,138 ​ 48,708 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues ​ $ 311,556 ​ $ 321,605 ​ $ 73,033 $ 18,559 ​ $ 724,753 Adjusted EBITDA ​ (5,944) ​ 63,630 ​ (6,072) ​ (49,431) ​ 2,183 Depreciation, depletion and amortization ​ 10,491 ​ 44,807 ​ 4,670 ​ 1,507 ​ 61,475 Accretion on asset retirement obligation ​ 6,990 ​ 972 ​ 695 ​ 1,335 ​ 9,992 Total assets ​ 247,990 ​ 740,451 ​ 108,238 ​ 705,710 ​ 1,802,389 Capital expenditures ​ 4,242 ​ 136,162 ​ 4,571 ​ 3,586 ​ 148,561 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Revenues ​ $ 422,878 ​ $ 514,507 ​ $ 184,183 ​ $ 3,837 ​ $ 1,125,405 Adjusted EBITDA ​ 35,279 ​ 193,470 ​ 17,041 ​ (32,972) ​ 212,818 Depreciation, depletion and amortization ​ 9,745 ​ 33,725 ​ 7,124 ​ 1,279 ​ 51,873 Accretion on asset retirement obligation ​ 6,271 ​ 1,061 ​ 1,207 ​ 1,735 ​ 10,274 Total assets ​ 236,527 ​ 605,657 ​ 136,899 ​ 910,447 ​ 1,889,530 Capital expenditures ​ 13,623 ​ 62,374 ​ 9,461 ​ 2,396 ​ 87,854
Schedule of Reconciliation of Net Income (Loss) to Adjusted EBITDA	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, ​ Six Months Ended June 30, ​ (In thousands) ​ 2020 ​ 2019 ​ 2020 ​ 2019 ​ Net income (loss) ​ $ (49,324) ​ $ 62,840 ​ $ (74,623) ​ $ 135,581 ​ Provision for (benefit from) income taxes ​ ​ 1,206 ​ ​ 91 ​ ​ (585) ​ ​ 161 ​ Interest expense, net ​ 1,730 ​ 2,287 ​ 3,859 ​ 4,576 ​ Depreciation, depletion and amortization ​ 30,167 ​ 26,535 ​ 61,475 ​ 51,873 ​ Accretion on asset retirement obligations ​ 4,986 ​ 5,137 ​ 9,992 ​ 10,274 ​ Costs related to proposed joint venture with Peabody Energy ​ 7,851 ​ 3,018 ​ 11,515 ​ 3,018 ​ Severance costs related to voluntary separation plan ​ 7,437 ​ — ​ 13,265 ​ — ​ Gain on property insurance recovery related to Mountain Laurel longwall ​ (14,518) ​ — ​ (23,518) ​ — ​ (Gain) loss on divestitures ​ ​ (1,369) ​ ​ 4,304 ​ ​ (1,369) ​ ​ 4,304 ​ Non-service related pension and postretirement benefit costs ​ 1,102 ​ 1,336 ​ 2,198 ​ 3,102 ​ Reorganization items, net ​ — ​ 16 ​ (26) ​ (71) ​ Adjusted EBITDA ​ $ (10,732) ​ $ 105,564 ​ $ 2,183 ​ $ 212,818 ​

Revenue Recognition (Tables)

Revenue Recognition (Tables)	6 Months Ended
	Jun. 30, 2020
Revenue Recognition
Schedule of effects of revenue recognition	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Corporate, ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Other ​ Other and ​ ​ ​ ​ ​ PRB ​ MET ​ Thermal ​ Eliminations ​ Consolidated ​ (in thousands) Three Months Ended June 30, 2020 ​ ​ ​ ​ ​ North America revenues ​ $ 133,096 ​ $ 40,137 ​ $ 31,149 ​ $ 6,177 ​ $ 210,559 Seaborne revenues ​ — ​ 98,814 ​ 10,148 ​ — ​ 108,962 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total revenues ​ $ 133,096 ​ $ 138,951 ​ $ 41,297 ​ $ 6,177 ​ $ 319,521 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended June 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ North America revenues ​ $ 210,149 ​ $ 54,896 ​ $ 47,885 ​ $ 623 ​ $ 313,553 Seaborne revenues ​ — ​ 206,349 ​ 50,320 ​ — ​ 256,669 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total revenues ​ $ 210,149 ​ $ 261,245 ​ $ 98,205 ​ $ 623 ​ $ 570,222 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ North America revenues ​ $ 311,375 ​ $ 69,860 ​ $ 59,733 ​ $ 18,559 ​ $ 459,527 Seaborne revenues ​ 181 ​ 251,745 ​ 13,300 ​ — ​ 265,226 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total revenues ​ $ 311,556 ​ $ 321,605 ​ $ 73,033 ​ $ 18,559 ​ $ 724,753 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, 2019 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ North America revenues ​ $ 422,878 ​ $ 99,562 ​ $ 94,414 ​ $ 3,837 ​ $ 620,691 Seaborne revenues ​ — ​ 414,945 ​ 89,769 ​ — ​ 504,714 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Total revenues ​ $ 422,878 ​ $ 514,507 ​ $ 184,183 ​ $ 3,837 ​ $ 1,125,405 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2020
Leases
Schedule of Information Related to Leases	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended June 30, ​ ​ ​ 2020 ​ ​ 2019 Operating lease information: ​ (In thousands) Operating lease cost ​ $ 905 ​ ​ ​ $ 917 ​ Operating cash flows from operating leases ​ 885 ​ ​ ​ ​ 871 ​ Weighted average remaining lease term in years ​ 5.38 ​ ​ ​ ​ 5.06 ​ Weighted average discount rate ​ 5.5 % ​ ​ ​ 5.6 % ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Financing lease information: ​ ​ ​ ​ ​ ​ ​ Financing lease cost ​ $ 393 ​ ​ ​ $ — ​ Operating cash flows from financing leases ​ 303 ​ ​ ​ ​ — ​ Weighted average remaining lease term in years ​ 4.75 ​ ​ ​ ​ — ​ Weighted average discount rate ​ 6.4 % ​ ​ ​ — %
Schedule of Future Minimum Lease Payments	Future minimum lease payments under non-cancellable leases as of June 30, 2020 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating ​ ​ Finance Year ​ Leases ​ ​ Leases ​ (In thousands) 2020 ​ $ 1,683 ​ ​ $ 605 2021 ​ 3,367 ​ ​ 1,210 2022 ​ 3,317 ​ ​ 1,210 2023 ​ 3,285 ​ ​ 1,210 2024 ​ 3,200 ​ ​ 1,210 Thereafter ​ 7,798 ​ ​ 2,111 Total minimum lease payments ​ $ 22,650 ​ ​ $ 7,556 Less imputed interest ​ (3,742) ​ ​ (1,273) ​ ​ ​ ​ ​ ​ ​ ​ Total lease liabilities ​ $ 18,908 ​ ​ $ 6,283 ​ ​ ​ ​ ​ ​ ​ ​ As reflected on balance sheet: ​ ​ ​ ​ ​ Accrued expenses and other current liabilities ​ $ 2,382 ​ ​ $ 833 Other noncurrent liabilities ​ 16,526 ​ ​ 5,450 ​ ​ ​ ​ ​ ​ ​ ​ Total lease liability ​ $ 18,908 ​ ​ $ 6,283

Joint Venture with Peabody En_2

Joint Venture with Peabody Energy (Details) - Implementation Agreement - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 18, 2019
Schedule of Equity Method Investments [Line Items]
Economic interest held				33.50%
Incurred expenses related to regulatory approval process	$ 7.9	$ 11.5	$ 3
Peabody Energy Corporation
Schedule of Equity Method Investments [Line Items]
Economic interest held				66.50%

Gain on Property Insurance Re_2

Gain on Property Insurance Recovery Related to Mountain Laurel Longwall (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020USD ($)item	Jun. 30, 2020USD ($)item
Business Interruption Loss [Line Items]
Gain on Business Interruption Insurance Recovery | $		$ 23,518
Longwall system's not recoverable | item	123	123
Mountain Laurel Longwall Operations
Business Interruption Loss [Line Items]
Gain on Business Interruption Insurance Recovery | $	$ 14,500	$ 23,500
Hydraulic Shields not recoverable | item	176	176

Severance Costs Related To Vo_2

Severance Costs Related To Voluntary Separation Plan (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020USD ($)employee	Jun. 30, 2020USD ($)employee
Severance Costs Related To Voluntary Separation Plan
Severance Costs | $	$ 7,437	$ 13,265
Number of corporate staff accepted voluntary separation package		53
Number of Employees accepted voluntary separation package	201	201

Divestitures (Details)

Divestitures (Details)	Sep. 14, 2017USD ($)company	Jun. 30, 2020USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2020USD ($)	Jun. 30, 2019USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Charge for bankruptcy claims					$ 4,300,000
Lone Mountain Processing LLC | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of mining companies | company	2
(Gain) loss on divestitures	$ (21,300,000)
Dal-Tex and Briar Branch Properties
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
(Gain) loss on divestitures		$ (1,369,000)	$ 4,304,000	$ (1,369,000)	$ 4,304,000
Dal-Tex and Briar Branch Properties | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from Divestiture of Interest in Subsidiaries and Affiliates, Total		0
Gain on disposal		$ 1,400,000

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	$ 640,536
Unrealized gains	(18,721)
Amounts reclassified from AOCI	(122)
Ending Balance	547,782
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	5,689
Ending Balance	(13,154)
Derivative instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	(2,564)
Unrealized gains	(2,974)
Amounts reclassified from AOCI	668
Ending Balance	(4,870)
Pension, postretirement and other post-employment benefits
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	8,273
Unrealized gains	(15,953)
Amounts reclassified from AOCI	(650)
Ending Balance	(8,330)
Available-for-sale securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning Balance	(20)
Unrealized gains	206
Amounts reclassified from AOCI	(140)
Ending Balance	$ 46

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income (Schedule of Reclassifications) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Revenues	$ 319,521	$ 570,222	$ 724,753	$ 1,125,405
Interest expense	(3,523)	(4,375)	(6,911)	(8,807)
Provision for (benefit from) income taxes	(1,206)	(91)	585	(161)
Interest and investment income	1,793	2,088	3,052	4,231
Net income (loss)	(49,324)	62,840	(74,623)	135,581
Reclassification out of Accumulated Other Comprehensive Income | Derivative instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Revenues	196	1,743	196	2,104
Interest expense	(648)	514	(864)	1,029
Provision for (benefit from) income taxes	0	0	0	0
Net income (loss)	(452)	2,257	(668)	3,133
Reclassification out of Accumulated Other Comprehensive Income | Pension, postretirement and other post-employment benefits
Accumulated Other Comprehensive Income (Loss) [Line Items]
Provision for (benefit from) income taxes	0	0	0	0
Amortization of actuarial gains (losses), net	232	0	466	0
Amortization of prior service credits	27		54
Pension settlement	134	429	130	429
Net income (loss)	393	429	650	429
Reclassification out of Accumulated Other Comprehensive Income | Available-for-sale securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Provision for (benefit from) income taxes	0	0	0	0
Interest and investment income	141	15	140	15
Net income (loss)	$ 141	$ 15	$ 140	$ 15

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Inventories
Coal	$ 67,702	$ 46,815
Repair parts and supplies	86,988	84,083
Inventories	154,690	130,898
Allowance for slow-moving and obsolete inventories	$ 2,400	$ 2,200

Investments in Available-for-_3

Investments in Available-for-Sale Securities (Schedule of Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Cost Basis	$ 67,191	$ 135,687
Available-for-sale, Gains	190	201
Available-for-sale, Losses	(144)	(221)
Available-for-sale, Fair Value	67,237	135,667
Available-for-sale, Short-Term Investments	67,237	135,667
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Cost Basis	14,030	35,044
Available-for-sale, Gains	24	1
Available-for-sale, Losses		(16)
Available-for-sale, Fair Value	14,054	35,029
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, Cost Basis	53,161	100,643
Available-for-sale, Gains	166	200
Available-for-sale, Losses	(144)	(205)
Available-for-sale, Fair Value	$ 53,183	$ 100,638

Investments in Available-for-_4

Investments in Available-for-Sale Securities (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Investments in Available-for-Sale Securities
Unrealized losses owned for less than 12 months	$ 12.5	$ 72.3
Unrealized losses owed for over a year	$ 5.1	$ 0

Derivatives (Narrative) (Detail

Derivatives (Narrative) (Details) gal in Millions, $ in Millions	6 Months Ended		12 Months Ended
	Dec. 31, 2020USD ($)	Jun. 30, 2020USD ($)$ / Optiongal	Dec. 31, 2021USD ($)	Dec. 31, 2019USD ($)
Derivative [Line Items]
Value of trading portfolio realized - gains (losses) | $	$ (0.3)
Current asset representing cash collateral posted | $		$ 3.9		$ 4.4
Derivative contracts expected to be reclassified from OCI into earnings | $		$ 0.2
Not Designated as Hedging Instrument | Heating Oil
Derivative [Line Items]
Quantities under derivative contracts (in gallons) | gal		6
Derivative, average price risk option strike price (in used per gallon) | $ / Option		1.74
Not Designated as Hedging Instrument | Diesel Purchases | Minimum
Derivative [Line Items]
Diesel fuel purchased annually (in gallons) | gal		30
Not Designated as Hedging Instrument | Diesel Purchases | Maximum
Derivative [Line Items]
Diesel fuel purchased annually (in gallons) | gal		35
Forecast
Derivative [Line Items]
Value of trading portfolio realized - gains (losses) | $			$ 0.3
NYMEX | Not Designated as Hedging Instrument | Diesel Purchases
Derivative [Line Items]
Quantities under derivative contracts (in gallons) | gal		4
Derivative, average price risk option strike price (in used per gallon) | $ / Option		1.03

Derivatives (Schedule of Price

Derivatives (Schedule of Price Risk Derivatives) (Details) T in Thousands	6 Months Ended
	Jun. 30, 2020T
Coal sales
Derivative [Line Items]
Derivatives held (in tons)	542
Coal purchases
Derivative [Line Items]
Derivatives held (in tons)	377
2020 | Coal sales
Derivative [Line Items]
Derivatives held (in tons)	542
2020 | Coal purchases
Derivative [Line Items]
Derivatives held (in tons)	377

Derivatives (Disclosure Of Fair

Derivatives (Disclosure Of Fair Value Of Derivatives) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative Assets	$ 26,039	$ 31,616
Derivative Liabilities	(20,380)	(25,870)
Effect of counterparty netting in derivative assets	(20,380)	(25,759)
Effect of counterparty netting in derivative liabilities	20,380	25,759
Derivative Asset	5,659	5,857
Derivative Liability		(111)
Net derivatives as classified in the balance sheets	5,659	5,746
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets	24,992	30,265
Derivative Liabilities	(19,529)	(24,908)
Not Designated as Hedging Instrument | Coal Contract
Derivative [Line Items]
Derivative Assets	12,910	18,467
Derivative Liabilities	(12,870)	(18,940)
Coal Contract | Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets	1,047	1,351
Derivative Liabilities	(851)	(962)
Coal Contract | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets	11,554	11,662
Derivative Liabilities	(6,659)	(5,856)
Heating oil - diesel purchases | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets	528	133
Derivative Liabilities		(112)
Natural gas | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative Assets	0	3
Derivative Liabilities	$ 0	$ 0

Derivatives (Net Derivatives As

Derivatives (Net Derivatives As Reflected On The Balance Sheets) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	$ 5,659	$ 5,746
Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet		(111)
Heating oil and coal | Other current assets
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	$ 5,659	$ 5,857

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, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value of coal derivatives and coal trading activities, net	$ 129	$ 8,400	$ (614)	$ 21,381
Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	1	3,670	4	8,341
Gains (Losses) Reclassified from Other Comprehensive Income into Income	(196)	1,743	(196)	2,101
Designated as Hedging Instrument | Coal sales | Coal Contract | Coal sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	440	4,010	599	9,247
Gains (Losses) Reclassified from Other Comprehensive Income into Income	(902)	1,743	(902)	2,787
Designated as Hedging Instrument | Coal purchases | Coal Contract | Coal purchases
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	(439)	(340)	(595)	(906)
Gains (Losses) Reclassified from Other Comprehensive Income into Income	706	0	706	(686)
Not Designated as Hedging Instrument | Coal Contract | Coal and natural gas realized and unrealized
Derivative Instruments, Gain (Loss) [Line Items]
Realized and Unrealized Gain (Loss) on Derivatives		(718)	221	(1,101)
Unrealized Gain (Loss) on Derivatives	129	9,137	(911)	22,562
Not Designated as Hedging Instrument | Coal Contract | Other operating (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives	2,756	(881)	4,357	(5,292)
Not Designated as Hedging Instrument | Natural gas | Coal and natural gas realized and unrealized
Derivative Instruments, Gain (Loss) [Line Items]
Realized and Unrealized Gain (Loss) on Derivatives		(19)	76	(80)
Not Designated as Hedging Instrument | Heating oil - diesel purchases | Other operating (income) expense, net
Derivative Instruments, Gain (Loss) [Line Items]
Heating oil realized and unrealized gains and losses	$ 328	$ (1,369)	$ (705)	$ (732)

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accrued Expenses and Other Current Liabilities
Payroll and employee benefits	$ 46,640	$ 50,929
Taxes other than income taxes	60,465	69,061
Interest	121	133
Workers' compensation	15,004	16,119
Asset retirement obligations	9,827	10,366
Other	11,247	10,559
Accrued expenses and other current liabilities	$ 143,304	$ 157,167

Debt and Financing Arrangemen_3

Debt and Financing Arrangements (Long term Debt) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Term loan	$ 289,427	$ 290,825
Other	65,085	25,007
Debt issuance costs	(4,956)	(5,013)
Total	349,556	310,819
Less: current maturities of debt	25,702	20,753
Long-term debt	323,854	$ 290,066
Term loan due 2024 ($291.0 million face value)
Debt Instrument [Line Items]
Debt instrument, face amount	$ 290,300

Debt and Financing Arrangemen_4

Debt and Financing Arrangements (Narrative) (Details)	Mar. 04, 2020USD ($)installment	Apr. 27, 2018	Mar. 07, 2017USD ($)	Jun. 30, 2020USD ($)	Jun. 30, 2020USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2019USD ($)	Apr. 27, 2017USD ($)
Line of Credit Facility [Line Items]
Additional availability for borrowings					$ 17,600,000
Fair value of derivative assets				$ 26,039,000	26,039,000			$ 31,616,000
Interest Rate Swap
Line of Credit Facility [Line Items]
Fair value of derivative assets				(5,100,000)	(5,100,000)
Interest rate swaps settlements gains				600,000	$ 900,000
Equipment financing arrangement
Line of Credit Facility [Line Items]
Interest rate	6.34%
Senior Notes | New Term Loan Debt Facility
Line of Credit Facility [Line Items]
Net cash proceeds of from debt issuances and other non-ordinary sales or dispositions (percent)			100
Default to indebtedness			$ 50,000,000
Default to surety, reclamation or similar bond			50,000,000
Default to uninsured judgment			50,000,000
Uninsured losses or proceedings against			50,000,000
Senior Notes | New Term Loan Debt Facility | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate						2.75%
Senior Notes | New Term Loan Debt Facility | LIBOR | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate						1.00%
Secured Debt | Equipment financing arrangement
Line of Credit Facility [Line Items]
Debt instrument, face amount	$ 53,600,000
Number of monthly payments | installment	48
Line of Credit | New Term Loan Debt Facility | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate						1.75%
New Term Loan Debt Facility | Senior Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount			$ 300,000,000
Percentage of face amount			99.50
Quarterly amortization payments			$ 750,000
Amount of voting equity interests of domestic subsidiaries guaranteed (percent)			100
Amount of voting equity interests of foreign owned subsidiaries guaranteed (percent)			65
New Term Loan Debt Facility | Senior Notes | LIBOR
Line of Credit Facility [Line Items]
Basis spread on variable rate					2.75%
Line of Credit | Secured Debt
Line of Credit Facility [Line Items]
Letters of credit outstanding				15,000,000	$ 15,000,000
Line of Credit | Secured Debt | Regions Bank
Line of Credit Facility [Line Items]
Debt instrument, face amount							$ 40,000,000
Maximum borrowing capacity						$ 50,000,000
Covenant minimum amount							$ 175,000,000		$ 175,000,000
Letters of credit outstanding				32,400,000	32,400,000
Current borrowing capacity						160,000,000
Percentage of coal inventory borrowing base							85
Percentage of parts and supplies inventory borrowing base							85
Percentage of clause borrowing base							35
Percent of eligible cash							100.00%
Facility size, increase						$ 10,000,000
Covenant amount (less than)							$ 250,000,000
Line of Credit | Secured Debt | LIBOR | Regions Bank | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate							2.00%
Line of Credit | Secured Debt | LIBOR | Regions Bank | Maximum
Line of Credit Facility [Line Items]
Percentage of clause borrowing base							2.50
Line of Credit | Secured Debt | Base Rate | Regions Bank | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate							1.00%
Line of Credit | Secured Debt | Base Rate | Regions Bank | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate							1.50%
Line of Credit | Secured Debt | Accounts Receivable Securitization Facility | Arch Receivable Company, LLC
Line of Credit Facility [Line Items]
Liquidity threshold, consecutive days		60 days
Liquidity threshold		364 days
Liquidity threshold, expiration period		60 days
Current borrowing capacity				$ 68,200,000	$ 68,200,000

Debt and Financing Arrangemen_5

Debt and Financing Arrangements (Interest rate derivatives) (Details) $ in Millions	Jun. 30, 2020USD ($)
June 30, 2020
Debt Instrument [Line Items]
Notional Amount	$ 200
Fixed Rate	2.249%
June 30, 2021
Debt Instrument [Line Items]
Notional Amount	$ 100
Fixed Rate	2.315%

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Taxes
Income tax provision at statutory rate	$ (10,105)	$ 13,216	$ (15,794)	$ 28,506
Percentage depletion allowance	(11,768)	(3,457)	(5,600)	(7,764)
State taxes, net of effect of federal taxes	(1,584)	831	(1,502)	1,843
Change in valuation allowance	19,531	(11,292)	20,381	(23,805)
Current expense associated with uncertain tax positions	5,132	844	3,101	1,437
AMT sequestration refund			(1,171)
Other, net		(51)	0	(56)
Provision for (benefit from) income taxes	1,206	$ 91	(585)	$ 161
Refund, AMT credits	37,400		37,400
Tax reserve for portion of refund subject to audit	$ 13,300		$ 13,300
Percentage of the total income tax refund amount subject to audit	40.00%

Fair Value Measurements (Summar

Fair Value Measurements (Summary Of Financial Assets And Liabilities Accounted For At Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Assets:
Investments in marketable securities	$ 67,237	$ 135,667
Derivatives	5,659
Total assets	72,896
Liabilities:
Derivatives	5,066
Level 1
Assets:
Investments in marketable securities	14,054
Derivatives	5,131
Total assets	19,185
Liabilities:
Derivatives	0
Level 2
Assets:
Investments in marketable securities	53,183
Derivatives	495
Total assets	53,678
Liabilities:
Derivatives	5,066
Level 3
Assets:
Investments in marketable securities	0
Derivatives	33
Total assets	33
Liabilities:
Derivatives	$ 0

Fair Value Measurements (Summ_2

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, 2020	Jun. 30, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 89	$ 61
Realized and unrealized gains recognized in earnings, net	(56)	(1,125)
Purchases		1,235
Issuances		(138)
Ending balance	$ 33	$ 33

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value of debt, including amounts classified as current	$ 308.9	$ 308.9	$ 308
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net unrealized losses related to level 3 financial instruments	$ (0.1)	$ (0.6)

Earnings per Common Share (Deta

Earnings per Common Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Weighted average shares outstanding:
Basic weighted average shares outstanding (in shares)	15,145,000	16,543,000	15,142,000	17,018,000
Effect of dilutive securities (in shares)		1,238,000		1,172,000
Diluted weighted average shares outstanding (in shares)	15,145,000	17,781,000	15,142,000	18,190,000
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities excluded			94,333
Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities excluded			165,167

Workers Compensation Expense (D

Workers Compensation Expense (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 29, 2020	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accrued Workers Compensation [Line Items]
Additional collateral amount	$ 71,100
Number of days required to submit additional collateral to retain self-insurance status	30 days
Occupational disease
Accrued Workers Compensation [Line Items]
Service cost		$ 1,891	$ 1,669	$ 3,782	$ 3,338
Interest cost		1,399	1,354	2,798	2,708
Net amortization(1)		298	0	595	0
Net benefit credit		3,588	3,023	7,175	6,046
Traumatic injury claims and assessments
Accrued Workers Compensation [Line Items]
Traumatic injury claims and assessments		2,100	2,410	4,282	4,554
Total workers' compensation expense
Accrued Workers Compensation [Line Items]
Total workers' compensation expense		$ 5,688	$ 5,433	$ 11,457	$ 10,600

Employee Benefit Plans (Details

Employee Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Defined benefit pension plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1,483	$ 2,259	$ 3,087	$ 4,517
Expected return on plan assets	(2,023)	(2,724)	(4,311)	(5,447)
Pension settlement	(134)	(429)	(130)	(429)
Amortization of prior service costs (credits)	(27)		(54)	0
Net benefit credit	(701)	(894)	(1,408)	(1,359)
Other postretirement benefits plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	106	120	212	240
Interest cost	653	877	1,306	1,753
Amortization of other actuarial losses (gains)	(529)		(1,059)	0
Net benefit credit	$ 230	$ 997	$ 459	$ 1,993

Segment Information (Schedule O

Segment Information (Schedule Of Operating Segment Results) (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2020USD ($)segment	Jun. 30, 2019USD ($)	Dec. 31, 2019USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			2
Revenues	$ 319,521	$ 570,222	$ 724,753	$ 1,125,405
Adjusted EBITDA	(10,732)	105,564	2,183	212,818
Depreciation, depletion and amortization	30,167	26,535	61,475	51,873
Accretion on asset retirement obligations	4,986	5,137	9,992	10,274
Total assets	1,802,389	1,889,530	1,802,389	1,889,530	$ 1,867,756
Capital expenditures	60,872	48,708	148,561	87,854
Operating Segments | PRB
Segment Reporting Information [Line Items]
Revenues	133,096	210,149	311,556	422,878
Adjusted EBITDA	(5,362)	14,696	(5,944)	35,279
Depreciation, depletion and amortization	5,283	4,880	10,491	9,745
Accretion on asset retirement obligations	3,495	3,135	6,990	6,271
Total assets	247,990	236,527	247,990	236,527
Capital expenditures	1,145	13,209	4,242	13,623
Operating Segments | MET
Segment Reporting Information [Line Items]
Revenues	138,951	261,245	321,605	514,507
Adjusted EBITDA	20,910	101,936	63,630	193,470
Depreciation, depletion and amortization	22,289	17,343	44,807	33,725
Accretion on asset retirement obligations	486	531	972	1,061
Total assets	740,451	605,657	740,451	605,657
Capital expenditures	57,514	31,150	136,162	62,374
Operating Segments | Other Thermal
Segment Reporting Information [Line Items]
Revenues	41,297	98,205	73,033	184,183
Adjusted EBITDA	(4,752)	10,922	(6,072)	17,041
Depreciation, depletion and amortization	2,333	3,689	4,670	7,124
Accretion on asset retirement obligations	347	603	695	1,207
Total assets	108,238	136,899	108,238	136,899
Capital expenditures	955	3,211	4,571	9,461
Corporate, Other and Eliminations
Segment Reporting Information [Line Items]
Revenues	6,177	623	18,559	3,837
Adjusted EBITDA	(21,528)	(21,990)	(49,431)	(32,972)
Depreciation, depletion and amortization	262	623	1,507	1,279
Accretion on asset retirement obligations	658	868	1,335	1,735
Total assets	705,710	910,447	705,710	910,447
Capital expenditures	$ 1,258	$ 1,138	$ 3,586	$ 2,396

Segment Information (Reconcilia

Segment Information (Reconciliation Segment Income To Consolidated Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Net income (loss)	$ (49,324)	$ 62,840	$ (74,623)	$ 135,581
Provision for (benefit from) income taxes	1,206	91	(585)	161
Interest expense, net	1,730	2,287	3,859	4,576
Depreciation, depletion and amortization	30,167	26,535	61,475	51,873
Accretion on asset retirement obligations	4,986	5,137	9,992	10,274
Costs related to proposed joint venture with Peabody Energy	7,851	3,018	11,515	3,018
Severance costs related to voluntary separation plan	7,437		13,265
Gain on property insurance recovery related to Mountain Laurel longwall	14,518		23,518
Non-service related pension and postretirement benefit costs	1,102	1,336	2,198	3,102
Reorganization items, net		16	(26)	(71)
Adjusted EBITDA	(10,732)	105,564	2,183	212,818
Dal-Tex and Briar Branch Properties
Segment Reporting Information [Line Items]
(Gain) loss on divestitures	$ (1,369)	$ 4,304	$ (1,369)	$ 4,304

Revenue Recognition (Disaggrega

Revenue Recognition (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 319,521	$ 570,222	$ 724,753	$ 1,125,405
Corporate, Other and Eliminations
Disaggregation of Revenue [Line Items]
Revenues	6,177	623	18,559	3,837
North America revenues
Disaggregation of Revenue [Line Items]
Revenues	210,559	313,553	459,527	620,691
North America revenues | Corporate, Other and Eliminations
Disaggregation of Revenue [Line Items]
Revenues	6,177	623	18,559	3,837
Seaborne revenues
Disaggregation of Revenue [Line Items]
Revenues	108,962	256,669	265,226	504,714
Seaborne revenues | Corporate, Other and Eliminations
Disaggregation of Revenue [Line Items]
Revenues	0	0	0	0
PRB | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	133,096	210,149	311,556	422,878
PRB | North America revenues | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	133,096	210,149	311,375	422,878
PRB | Seaborne revenues | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	0	0	181	0
MET | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	138,951	261,245	321,605	514,507
MET | North America revenues | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	40,137	54,896	69,860	99,562
MET | Seaborne revenues | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	98,814	206,349	251,745	414,945
Other Thermal | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	41,297	98,205	73,033	184,183
Other Thermal | North America revenues | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	31,149	47,885	59,733	94,414
Other Thermal | Seaborne revenues | Operating Segments
Disaggregation of Revenue [Line Items]
Revenues	$ 10,148	$ 50,320	$ 13,300	$ 89,769

Revenue Recognition (Narrative)

Revenue Recognition (Narrative) (Details) T in Millions	Jun. 30, 2020T
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligations, fixed price contracts (in tons)	36.2
Remaining performance obligations, variable price contracts (in tons)	2.5
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligations, fixed price contracts (in tons)	69
Remaining performance obligations, variable price contracts (in tons)	4.5

Leases (Narrative) (Details)

Leases (Narrative) (Details) $ in Millions	Jun. 30, 2020USD ($)
Lessee, Lease, Description [Line Items]
Right-of-use operating lease asset	$ 18.2
Finance Lease, Right-of-Use Asset	$ 6.2
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other Assets, Noncurrent
Minimum
Lessee, Lease, Description [Line Items]
Operating lease, remaining lease terms	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating lease, remaining lease terms	7 years

Leases (Information Related to

Leases (Information Related to Leases) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Lease information:
Operating lease cost	$ 905	$ 917
Operating cash flows from operating leases	$ 885	$ 871
Weighted average remaining lease term in years	5 years 4 months 17 days	5 years 21 days
Weighted average discount rate	5.50%	5.60%
Financing lease cost	$ 393
Operating cash flows from financing leases	$ 303
Weighted average discount rate	6.40%

Leases (Future Minimum Lease Pa

Leases (Future Minimum Lease Payments) (Details) $ in Thousands	Jun. 30, 2020USD ($)
Operating Leases
2020	$ 1,683
2021	3,367
2022	3,317
2023	3,285
2024	3,200
Thereafter	7,798
Total minimum lease payments	22,650
Less imputed interest	(3,742)
Total operating lease liability	18,908
As reflected on balance sheet:
Accrued expenses and other current liabilities	2,382
Other noncurrent liabilities	16,526
Total operating lease liability	18,908
Finance Leases
2020	605
2021	1,210
2022	1,210
2023	1,210
2024	1,210
Thereafter	2,111
Total minimum lease payments	7,556
Less imputed interest	(1,273)
Total finance lease liability	6,283
As reflected on balance sheet:
Accrued expenses and other current liabilities	833
Other noncurrent liabilities	5,450
Finance Lease, Liability	$ 6,283

Subsequent Events (Details)

Subsequent Events (Details) - Subsequent Event - Bonds $ in Millions	Jul. 02, 2020USD ($)
Subsequent Event [Line Items]
Term loan, face value	$ 53.1
Fixed interest rate	5.00%
Cash proceed	$ 30