Supplemental Disclosures (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Supplemental Disclosures [Line Items]
Total accrued liabilities	$ 132,853	$ 200,695
Accrued evaluated and unproved and unevaluated property costs
Supplemental Disclosures [Line Items]
Total accrued liabilities	53,684	72,376
Accrued midstream properties costs
Supplemental Disclosures [Line Items]
Total accrued liabilities	35,953	46,402
Accrued lease operating expenses
Supplemental Disclosures [Line Items]
Total accrued liabilities	22,480	18,223
Accrued interest on debt
Supplemental Disclosures [Line Items]
Total accrued liabilities	2,969	18,569
Accrued asset retirement obligations
Supplemental Disclosures [Line Items]
Total accrued liabilities	596	619
Accrued partners’ share of joint interest charges
Supplemental Disclosures [Line Items]
Total accrued liabilities	7,294	14,322
Accrued payable related to purchased natural gas
Supplemental Disclosures [Line Items]
Total accrued liabilities	2,152	17,806
Other
Supplemental Disclosures [Line Items]
Total accrued liabilities	$ 7,725	$ 12,378