Assets Held for Sale and Discontinued Operations - Summary of Results of Operations for Discontinued Operations (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Discontinued Operations And Disposal Groups [Abstract]
Revenues	$ 698	$ 1,874	$ 2,948	$ 5,402
Impairment of proved oil and natural gas properties			(6,849)
Depreciation, depletion, amortization and accretion	(182)	(168)	(523)	(380)
Other operating expenses	(1,317)	(2,943)	(5,668)	(3,738)
Other income				2
Income (loss) from discontinued operations, net of tax	$ (801)	$ (1,237)	$ (10,092)	$ 1,286