Other Liabilities (Details) - Non Current Liabilities - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule of Other Liabilities [Line Items]
Production Tax Liability	$ 87,170	$ 65,592
Deferred oil gathering credits	16,583	18,090
Deferred Midstream gathering credits	162,112	168,478
Operating and Finance Lease Liability, Noncurrent	7,760	10,763
Other Accrued Liabilities	751	1,111
Other Accrued Liabilities, Noncurrent	$ 274,376	$ 264,034