Income Taxes - Components of Tax Benefit (Provision) Allocated to Continuing Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Current:
Federal	$ 0	$ (8)
State	(28)	(30)
Foreign	(11)	(9)
Sub-total	(39)	(47)
Deferred:
Federal	0	253
State	0	0
Foreign	0	0
Sub-total	0	253
Total tax benefit (provision)	$ (39)	$ 206

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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