Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Oil and natural gas properties	$ 10,026,836	$ 9,169,156
Office furniture and fixtures	42,581	37,369
Buildings	44,565	44,565
Land	5,521	4,820
Total property and equipment	10,119,503	9,255,910
Accumulated depletion, depreciation, amortization and impairment	(4,640,098)	(4,153,733)
Property and equipment, net	$ 5,479,405	$ 5,102,177

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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- Definition

Oil and gas properties, gross, carried under the full cost method.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business 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 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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