CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cash Flows from Operating Activities:
Net Income	$ 2,475	$ 20,303
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Depreciation, Depletion and Amortization	54,943	50,724
Loss (Gain) on Sale of Assets	14	(339)
Stock/Unit-Based Compensation	5,014	7,450
Amortization of Debt Issuance Costs	1,444	1,976
(Gain) Loss on Debt Extinguishment	(16,833)	23,143
Deferred Income Taxes	1,908	(850)
Equity in Earnings of Affiliates	315	0
Changes in Operating Assets:
Accounts and Notes Receivable	23,064	(16,850)
Inventories	(4,507)	(6,242)
Prepaid Expenses and Other Assets	4,845	2,761
Changes in Other Assets	191	10,080
Changes in Operating Liabilities:
Accounts Payable	(15,726)	(10,695)
Other Operating Liabilities	3,899	12,419
Changes in Other Liabilities	(9,646)	(11,709)
Net Cash Provided by Operating Activities	51,400	82,171
Cash Flows from Investing Activities:
Capital Expenditures	(27,178)	(34,171)
Proceeds from Sales of Assets	0	311
Net Cash Used in Investing Activities	(27,178)	(33,860)
Cash Flows from Financing Activities:
Proceeds from Finance Lease Obligations	16,293	0
Payments on Finance Lease Obligations	(4,899)	(4,537)
Distributions to Noncontrolling Interest	(5,575)	(5,559)
Shares/Units Withheld for Taxes	(772)	(4,743)
Debt-Related Financing Fees	(643)	(18,514)
Net Cash Used in Financing Activities	(25,688)	(136,478)
Net Decrease in Cash and Cash Equivalents and Restricted Cash	(1,466)	(88,167)
Cash and Cash Equivalents and Restricted Cash at Beginning of Period	80,293	264,935
Cash and Cash Equivalents and Restricted Cash at End of Period	78,827	176,768
Non-Cash Investing and Financing Activities:
Finance Lease	7,023	0
Longwall Shield Rebuild	9,129	0
Term Loan A
Cash Flows from Financing Activities:
Proceeds from Term Loan A	0	26,250
Payments on Debt	(3,750)	0
Term Loan B
Cash Flows from Financing Activities:
Payments on Debt	(688)	(122,375)
11.00% Senior Secured Second Lien Notes due November 2025
Cash Flows from Financing Activities:
Payments on Debt	(25,480)	(7,000)
Other Asset-Backed Financing Arrangements
Cash Flows from Financing Activities:
Payments on Debt	$ (174)	$ 0

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