Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Oil and gas properties:
Proved properties	$ 7,665,886	$ 8,301,679
Unproved properties	212,030	210,161
Total oil and gas properties	7,877,916	8,511,840
Accumulated depletion	(4,512,941)	(4,780,826)
Oil and gas properties, net	3,364,975	3,731,014
Other property	68,299	68,255
Accumulated depreciation	(65,785)	(65,485)
Other property, net	2,514	2,770
Property and equipment, net	3,367,489	$ 3,733,784	$ 4,413,056
TEN FPSO Lease
Oil and gas properties:
Proved properties	$ 85,400

Amount of accumulated depreciation, depletion, and amortization of oil and gas property accounted for under successful efforts method.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount, before accumulated depreciation, depletion, amortization, and impairment, of oil and gas properties with proved reserve accounted for under successful efforts method.

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Amount, before accumulated depreciation, depletion, amortization, and impairment, of oil and gas properties with unproved reserve accounted for under successful efforts method.

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