Summary of Provision for Income Taxes from Continuing Operations (Detail) - USD ($) $ in Thousands	2 Months Ended	4 Months Ended	8 Months Ended	12 Months Ended
	Sep. 12, 2016	Dec. 31, 2016	Sep. 12, 2016	Dec. 31, 2018	Dec. 31, 2017
Provisions for Income Taxes [Line Items]
State				$ 500
Income tax benefit				4,900
Predecessor [Member]
Provisions for Income Taxes [Line Items]
Federal			$ 0
Current income tax expense (benefit), total			0
Federal			0
State			0
Deferred income tax benefit, total			0
Income tax benefit			$ 0
Successor [Member]
Provisions for Income Taxes [Line Items]
Federal		$ 0		(2,471)	$ 0
Current income tax expense (benefit), total	$ 0			(2,471)	0
Federal		0		2,471	(4,943)
State		0		523	0
Deferred income tax benefit, total		0		2,994	(4,943)
Income tax benefit		$ 0		$ 523	$ (4,943)