Condensed Consolidated Statements of Cash Flows - Unaudited - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Cash Flows [Abstract]
Net income	$ 69,498	$ 135,083
Adjustments to reconcile net income to net cash provided by operating activities
Unrealized loss (gain) on derivatives	43,423	(136,430)
Depletion, depreciation and amortization	74,863	90,707
Accretion of asset retirement obligations	500	476
Stock-based compensation expense	855	3,794
Deferred income tax provision	2,840	39,957
Amortization of debt issuance cost	724	684
Changes in operating assets and liabilities
Accounts receivable	(39,680)	36,342
Lease and well equipment inventory	112	(1,296)
Prepaid expenses and other current assets	(802)	174
Other long-term assets	19	1,749
Accounts payable, accrued liabilities and other current liabilities	8,560	(58,562)
Royalties payable	5,741	384
Advances from joint interest owners	2,809	(3,598)
Other long-term liabilities	(67)	(92)
Net cash provided by operating activities	169,395	109,372
Investing activities
Drilling, completion and equipping capital expenditures	(85,986)	(133,170)
Acquisition of oil and natural gas properties	(6,676)	(40,824)
Midstream capital expenditures	(16,380)	(73,439)
Expenditures for other property and equipment	(133)	(787)
Proceeds from sale of assets	280	0
Net cash used in investing activities	(108,895)	(248,220)
Financing activities
Repayments of borrowings under Credit Agreement	(100,000)	0
Proceeds from Lines of Credit	0	60,000
Repayments of borrowings under San Mateo Credit Facility	(11,000)	0
Borrowings under San Mateo Credit Facility	11,000	19,500
Cost to amend credit facilities	0	(660)
Dividends paid	(2,913)	0
Contributions related to formation of San Mateo	15,376	14,700
Contributions from non-controlling interest owners of less-than-wholly-owned subsidiaries	0	50,000
Distributions to non-controlling interest owners of less-than-wholly-owned subsidiaries	(14,210)	(11,515)
Taxes paid related to net share settlement of stock-based compensation	(1,721)	(1,336)
Other	(158)	(174)
Net cash (used in) provided by financing activities	(103,626)	130,515
Decrease in cash and restricted cash	(43,126)	(8,333)
Cash and restricted cash at beginning of period	91,383	65,128
Cash and restricted cash at end of period	$ 48,257	$ 56,795