Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating activities
Net income	$ 275,461	$ 679,435
Adjustments to reconcile to cash from operating activities:
Depreciation, depletion and amortization	71,556	64,990
Accretion on asset retirement obligations	10,585	8,860
Deferred income taxes	49,824
Employee stock-based compensation expense	13,206	14,552
Amortization relating to financing activities	884	1,130
Gain on disposals and divestitures, net	(393)	(697)
Reclamation work completed	(11,757)	(8,204)
Contribution to fund for asset retirement obligations	(2,664)	(80,000)
Changes in:
Receivables	(13,057)	(138,155)
Inventories	(40,295)	(56,018)
Accounts payable, accrued expenses and other current liabilities	(53,729)	37,083
Income taxes, net	(828)	427
Coal derivative assets and liabilities, including margin account	1,407	17,710
Other	22,686	20,054
Cash provided by operating activities	322,886	561,167
Investing activities
Capital expenditures	(76,606)	(53,157)
Minimum royalty payments	(1,113)	(1,000)
Proceeds from disposals and divestitures	439	1,547
Purchases of short-term investments	(13,772)
Proceeds from sales of short-term investments	17,488	14,450
Investments in and advances to affiliates, net	(9,927)	(4,027)
Cash used in investing activities	(83,491)	(42,187)
Financing activities
Payments on term loan due 2024	(1,500)	(272,288)
Payments on convertible debt	(58,430)	(129,941)
Net payments on other debt	(24,849)	(19,939)
Purchases of treasury stock	(93,803)
Dividends paid	(111,913)	(154,567)
Payments for taxes related to net share settlement of equity awards	(27,217)	(4,908)
Proceeds from warrants exercised	43,750	19,412
Cash used in financing activities	(273,962)	(562,231)
Decrease in cash and cash equivalents, including restricted cash	(34,567)	(43,251)
Cash and cash equivalents, including restricted cash, beginning of period	237,159	326,295
Cash and cash equivalents, including restricted cash, end of period	202,592	283,044
Cash and cash equivalents, including restricted cash, end of period
Cash and cash equivalents	201,492	281,944
Restricted Cash	1,100	1,100
Cash and cash equivalents, including restricted cash	$ 202,592	$ 283,044