Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Other Liabilities Disclosure [Abstract]
Royalties	$ 152,498	$ 72,401
Accrued Interest	36,035	26,549
Short-Term Incentive Compensation	19,591	20,340
Deferred Revenue	18,984	10,986
Transportation Charges	15,808	15,969
Accrued Other Taxes	12,681	10,580
Accrued Payroll & Benefits	5,747	5,009
Litigation Contingency	1,200	2,025
Purchased Gas Payable	757	1,528
Other	15,435	23,144
Current Portion of Long-Term Liabilities:
Asset Retirement Obligations	7,154	8,455
Salary Retirement	1,842	1,787
Total Other Accrued Liabilities	$ 287,732	$ 198,773