Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Operating activities
Net income (loss)	$ (25,299)	$ 72,741
Adjustments to reconcile to cash provided by operating activities:
Depreciation, depletion and amortization	31,308	25,273
Accretion on asset retirement obligations	5,006	5,137
Amortization of sales contracts, net		65
Employee stock-based compensation expense	3,962	5,651
Gains on disposals and divestitures, net	(214)	(475)
Amortization relating to financing activities	971	907
Property insurance recovery related to Mountain Laurel longwall	(9,000)
Changes in:
Receivables	23,728	7,410
Inventories	(19,088)	(20,137)
Accounts payable, accrued expenses and other current liabilities	(39,201)	(17,861)
Income taxes, net	(1,073)	76
Other	16,865	6,262
Cash provided by (used in) operating activities	(12,035)	84,984
Investing activities
Capital expenditures	(87,690)	(39,147)
Minimum royalty payments	(62)	(63)
Proceeds from disposals and divestitures	233	608
Purchases of short term investments	(17,196)	(27,902)
Proceeds from sales of short term investments	23,221	26,500
Investments in and advances to affiliates, net	(739)	(2,196)
Property insurance recovery related to Mountain Laurel longwall	7,353
Cash used in investing activities	(74,880)	(42,200)
Financing activities
Payments on term loan due 2024	(750)	(750)
Proceeds from equipment financing	53,611
Net payments on other debt	(5,544)	(4,633)
Debt financing costs	(422)
Dividends paid	(7,645)	(7,839)
Purchases of treasury stock		(75,749)
Payments for taxes related to net share settlement of equity awards	(198)
Cash used in financing activities	39,052	(88,971)
Decrease in cash and cash equivalents, including restricted cash	(47,863)	(46,187)
Cash and cash equivalents, including restricted cash, beginning of period	153,020	264,937
Cash and cash equivalents, including restricted cash, end of period	105,157	218,750
Cash and cash equivalents, including restricted cash, end of period
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