Supplemental Oil and Natural Gas Information (unaudited) - Summary of Capitalized Costs (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Oil and natural gas properties:
Unproved properties	$ 508,576	$ 482,475
Proved properties	2,783,232	2,188,233
Total oil and natural gas properties	3,291,808	2,670,708
Less accumulated depreciation, depletion and amortization	(1,532,127)	(1,380,650)
Net oil and natural gas properties	$ 1,759,681	$ 1,290,058

Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities.

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The sum of capitalized costs relating to oil and gas producing activities before accounting for accumulated depreciation.

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Net amount of capitalized costs relating to oil and gas producing activities.

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Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table.

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Capitalized costs of unproved properties incurred for any combination mineral interests acquisitions and other costs not previously disclosed within this table.

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