Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating activities
Net income	$ 198,108	$ 271,872
Adjustments to reconcile to cash from operating activities:
Depreciation, depletion and amortization	35,479	32,210
Accretion on asset retirement obligations	5,292	4,430
Deferred income taxes	35,548
Employee stock-based compensation expense	6,767	8,203
Amortization relating to financing activities	450	770
Gain on disposals and divestitures, net	(279)	(352)
Reclamation work completed	(3,887)	(4,278)
Contribution to fund for asset retirement obligations	(1,141)	(20,000)
Changes in:
Receivables	(57,968)	(399)
Inventories	(48,140)	(47,263)
Accounts payable, accrued expenses and other current liabilities	(63,508)	14,115
Income taxes, net	1,491	442
Coal derivative assets and liabilities, including margin account	(1,462)	15,833
Other	19,371	17,356
Cash provided by operating activities	126,121	292,939
Investing activities
Capital expenditures	(30,541)	(22,288)
Minimum royalty payments	(113)
Proceeds from disposals and divestitures	343	360
Purchases of short-term investments	(2,930)
Proceeds from sales of short-term investments	8,000	14,450
Investments in and advances to affiliates, net	(4,329)	(2,088)
Cash used in investing activities	(29,570)	(9,566)
Financing activities
Payments on term loan due 2024	(750)	(271,537)
Payments on convertible debt	(58,430)
Net payments on other debt	(12,647)	(10,134)
Dividends paid	(66,902)	(3,851)
Purchases of treasury stock	(20,806)
Payments for taxes related to net share settlement of equity awards	(27,055)	(4,827)
Proceeds from warrants exercised	43,719	506
Cash used in financing activities	(142,871)	(289,843)
Decrease in cash and cash equivalents, including restricted cash	(46,320)	(6,470)
Cash and cash equivalents, including restricted cash, beginning of period	237,159	326,295
Cash and cash equivalents, including restricted cash, end of period	190,839	319,825
Cash and cash equivalents, including restricted cash, end of period
Cash and cash equivalents	189,739	318,725
Restricted Cash	1,100	1,100
Cash and cash equivalents, including restricted cash	$ 190,839	$ 319,825