Oil and Natural Gas Properties - Schedule of Oil and Natural Gas Properties (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Oil and Gas Property [Abstract]
Proved	$ 1,276,950	$ 750,492
Unproved	1,152,942	1,126,459
Less: accumulated depreciation, depletion, amortization and impairment	(183,557)	(78,307)
Oil and natural gas properties, net	$ 2,246,335	$ 1,798,644

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Amount of accumulated depreciation, depletion, amortization and impairment of oil and gas property carried under the successful effort method.

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Oil and gas properties net of accumulated depreciation, depletion, amortization, impairment, and abandonment, carried under the successful effort method.

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Oil and Gas properties with proved reserves under the successful effort method.

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Oil and Gas properties with unproved reserves under the successful effort method.

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