CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues
Revenues	$ 4,710,089	$ 3,124,870	$ 5,401,516
Operating expenses
Cost of revenues (excluding depreciation)	4,338,474	2,947,697	4,803,589
Operating expense (excluding depreciation)	299,669	277,427	312,899
Depreciation, depletion, and amortization	94,241	90,036	86,121
Impairment expense	1,838	85,806	0
Gain on sale of assets, net	(64,697)	0	0
General and administrative expense (excluding depreciation)	48,096	41,288	46,223
Acquisition and integration costs	87	614	4,704
Total operating expenses	4,717,708	3,442,868	5,253,536
Operating income (loss)	(7,619)	(317,998)	147,980
Other income (expense)
Interest expense and financing costs, net	(66,493)	(70,222)	(74,839)
Debt extinguishment and commitment costs	(8,144)	0	(11,587)
Gain on curtailment of pension obligation	2,032	0	0
Other income (expense), net	(52)	1,049	2,516
Change in value of common stock warrants	0	4,270	(3,199)
Equity losses from Laramie Energy, LLC	0	(46,905)	(89,751)
Total other expense, net	(72,657)	(111,808)	(176,860)
Loss before income taxes	(80,276)	(429,806)	(28,880)
Income tax benefit (expense)	(1,021)	20,720	69,689
Net income (loss)	$ (81,297)	$ (409,086)	$ 40,809
Income (loss) per share
Basic (USD per share)	$ (1.40)	$ (7.68)	$ 0.80
Diluted (USD per share)	$ (1.40)	$ (7.68)	$ 0.80
Weighted-average number of shares outstanding
Basic (in shares)	58,268	53,295	50,352
Diluted (in shares)	58,268	53,295	50,470