Oil and Gas Properties - Summary of Oil and Gas Properties (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Oil And Gas Exploration And Production Industries Disclosures [Abstract]
Proved properties and equipment	$ 750,226	$ 538,695
Unproved properties	78,655	72,584
Less accumulated depletion and impairment	(257,718)	(172,051)
Total oil and gas properties	$ 571,163	$ 439,228

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

+ References

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-Publisher FASB
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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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