Derivative Financial Instruments - Schedule of Location and Fair Value Amounts of All Derivative Instruments (Details) - Derivatives Not Designated as Hedging Contracts - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivative asset - current | Commodity contracts
Derivative Asset [Abstract]
Gross Recognized Assets	$ 1,340	$ 11,071
Gross Amounts Offset, Assets	(1,323)	(3,562)
Total financial assets	17	7,509
Derivative liability - current | Commodity contracts
Derivative Liability [Abstract]
Gross Recognized Liabilities	68,707	4,492
Gross Amounts Offset, Liabilities	(1,323)	(3,562)
Total financial liabilities	67,384	930
Derivative liability - current | Interest rate swaps
Derivative Liability [Abstract]
Gross Recognized Liabilities	191	205
Gross Amounts Offset, Liabilities	0	0
Total financial liabilities	191	205
Derivative asset - noncurrent | Commodity contracts
Derivative Asset [Abstract]
Gross Recognized Assets	285	396
Gross Amounts Offset, Assets	(277)	0
Total financial assets	8	396
Derivative asset - noncurrent | Interest rate swaps
Derivative Asset [Abstract]
Gross Recognized Assets	445	0
Gross Amounts Offset, Assets	0	0
Total financial assets	445	0
Derivative liability - noncurrent | Commodity contracts
Derivative Liability [Abstract]
Gross Recognized Liabilities	8,007	0
Gross Amounts Offset, Liabilities	(277)	0
Total financial liabilities	7,730	0
Derivative liability - noncurrent | Interest rate swaps
Derivative Liability [Abstract]
Gross Recognized Liabilities	0	173
Gross Amounts Offset, Liabilities	0	0
Total financial liabilities	$ 0	$ 173