Supplemental Disclosures (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Supplemental Disclosures [Line Items]
Total accrued liabilities	$ 173,113	$ 170,855
Accrued evaluated and unproved and unevaluated property costs
Supplemental Disclosures [Line Items]
Total accrued liabilities	101,955	86,318
Accrued midstream property costs
Supplemental Disclosures [Line Items]
Total accrued liabilities	12,907	16,808
Accrued lease operating expenses
Supplemental Disclosures [Line Items]
Total accrued liabilities	19,015	12,705
Accrued interest on debt
Supplemental Disclosures [Line Items]
Total accrued liabilities	3,087	22,448
Accrued asset retirement obligations
Supplemental Disclosures [Line Items]
Total accrued liabilities	1,655	1,350
Accrued partners’ share of joint interest charges
Supplemental Disclosures [Line Items]
Total accrued liabilities	15,457	17,037
Other
Supplemental Disclosures [Line Items]
Total accrued liabilities	$ 19,037	$ 14,189