Income Tax - Schedule of Effective Income Tax Rate Reconciliation (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income (loss) before income taxes	$ 18,826	$ 8,525	$ (206,189)
Statutory rate	21.00%	35.00%	35.00%
Income tax benefit computed at statutory rate	$ 3,953	$ 2,984	$ (72,166)
Reconciling items:
State income taxes			546
Other, net	54	50	854
Share-based compensation	1,201	(576)
Executive compensation limitation	268	496
Change in valuation allowance	$ (5,476)	(145,449)	71,312
Change in Federal tax rate		$ 142,495
Total income tax expense (benefit)			$ 546

Income tax reconciliation change in federal tax rate.

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Income tax reconciliation executive compensation limitation.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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