Supplemental Information On Oil And Gas Exploration And Production Activities (Unaudited) - Summary of Capitalized Costs, Impairment, and Depreciation, Depletion and Amortization (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Oil and gas properties, successful efforts method:
Accumulated impairment	$ (168,000)	$ (121,100)
Proved properties, net of accumulated impairments	1,017,496	970,808
Unproved properties, net of accumulated impairments	233,767	260,271
Land	5,382	5,382
Total oil and gas properties, net of accumulated impairments	1,256,645	1,236,461
Accumulated depreciation, depletion and amortization	(291,213)	(195,567)
Net oil and gas properties	965,432	1,040,894
Proved property
Oil and gas properties, successful efforts method:
Proved properties	1,118,148	1,046,208
Accumulated impairment	(100,652)	(75,400)
Proved properties, net of accumulated impairments	1,017,496	970,808
Unproved property
Oil and gas properties, successful efforts method:
Accumulated impairment	(67,316)	(45,690)
Unproved properties	301,083	305,961
Unproved properties, net of accumulated impairments	$ 233,767	$ 260,271