CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net (loss) income	$ (199,065,000)	$ 50,523,000
Adjustments to reconcile net (loss) income to net cash provided by (used in) operating activities:
Depreciation, depletion and amortization	108,746,000	75,904,000
Amortization of debt issuance costs	3,990,000	3,786,000
Impairment of oil and gas properties	289,085,000	0
Stock-based compensation expense	11,397,000	6,277,000
Deferred income taxes	(702,000)	19,294,000
Increase in allowance for doubtful accounts	1,112,000	427,000
Other operating expenses	2,145,000	4,744,000
Derivative activities:
Total (gains) losses	(160,222,000)	2,796,000
Cash settlements on derivatives	106,975,000	26,731,000
Changes in assets and liabilities:
Decrease (increase) in accounts receivable	21,985,000	(6,690,000)
Increase in other assets	(919,000)	(2,073,000)
Decrease in accounts payable and accrued expenses	(29,882,000)	(12,344,000)
Decrease in other liabilities	(10,226,000)	(5,108,000)
Net cash provided by operating activities	144,419,000	164,267,000
Capital expenditures:
Development of oil and natural gas properties	(58,370,000)	(157,281,000)
Purchases of other property and equipment	(3,951,000)	(12,394,000)
Changes in capital investment accruals	(10,347,000)	(4,613,000)
Acquisition of properties and equipment and other	(2,104,000)	(2,819,000)
Proceeds from sale of property and equipment and other	250,000	969,000
Net cash used in investing activities	(74,522,000)	(176,138,000)
Cash flows from financing activities:
Proceeds from sale of property and equipment and other	228,900,000	252,182,000
Repayments on RBL credit facility	(230,750,000)	(242,182,000)
Dividends paid on common stock	(19,447,000)	(29,431,000)
Purchase of treasury stock	0	(36,139,000)
Shares withheld for payment of taxes on equity awards and other	(980,000)	(1,239,000)
Net cash used in financing activities	(22,277,000)	(56,809,000)
Net increase (decrease) in cash and cash equivalents	47,620,000	(68,680,000)
Cash and cash equivalents:
Beginning	0	68,680,000
Ending	$ 47,620,000	$ 0