Condensed Consolidated Income Statements - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Condensed Consolidated Income Statements
Revenues	$ 863,835	$ 594,412	$ 2,865,129	$ 1,402,345
Costs, expenses and other operating
Cost of sales (exclusive of items shown separately below)	610,027	423,826	1,758,012	1,089,061
Depreciation, depletion and amortization	33,958	30,760	98,948	84,441
Accretion on asset retirement obligations	4,430	5,437	13,290	16,311
Change in fair value of coal derivatives and coal trading activities, net	(12,252)	19,641	5,144	28,931
Selling, general and administrative expenses	26,107	21,081	79,271	66,679
Other operating expense (income), net	16,997	(1,731)	18,796	(11,344)
Costs, expenses and other operating	679,267	499,014	1,973,461	1,274,079
Income from operations	184,568	95,398	891,668	128,266
Interest expense, net
Interest expense	(4,060)	(6,151)	(16,245)	(13,220)
Interest and investment income	2,224		2,776	474
Interest expense, net	(1,836)	(6,151)	(13,469)	(12,746)
Income before nonoperating expenses	182,732	89,247	878,199	115,520
Nonoperating expenses
Non-service related pension and postretirement benefit costs	(857)	(1,186)	(2,189)	(3,252)
Net loss resulting from early retirement of debt	(394)		(14,143)
Nonoperating expenses	(1,251)	(1,186)	(16,332)	(3,252)
Income before income taxes	181,481	88,061	861,867	112,268
Provision for (benefit from) income taxes	474	(1,082)	1,424	1,301
Net income	$ 181,007	$ 89,143	$ 860,443	$ 110,967
Net income per common share
Basic earnings per share (in dollars per share)	$ 9.84	$ 5.83	$ 50.97	$ 7.26
Diluted earnings per share (in dollars per share)	$ 8.68	$ 4.92	$ 41.00	$ 6.49
Weighted average shares outstanding
Basic weighted average shares outstanding (in shares)	18,396	15,302	16,881	15,293
Diluted weighted average shares outstanding (in shares)	20,908	18,105	21,210	17,101
Dividends declared per common share (in dollars per share)	$ 6.00		$ 14.36