Supplemental Oil and Natural Gas Information - Summary of Costs Incurred in Oil and Natural Gas Properties (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Acquisition costs:
Unproved properties	$ 107,862	$ 57,498	$ 24,764
Proved properties	4,072
Development cost	239,467	257,119	150,778
Exploration cost	20,957	18,791	20,127
Total acquisition, development and exploration costs	$ 372,358	$ 333,408	$ 195,669

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Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have proved reserves.

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Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have unproved reserves.

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Development costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

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Exploration costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

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Amount of costs incurred related to oil and gas property acquisition, exploration and development activities, including capitalized costs and costs charged to expense.

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