Income Taxes - Components of Tax Expense (Benefit) Allocated to Continuing Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal		$ (2)	$ (3,378)
State	$ (11)	49	1
Foreign	21	19	5
Sub-total	10	66	(3,372)
Deferred:
Federal			3,516
State			508
Sub-total			4,024
Total tax provision (benefit)	$ 10	$ 66	$ 652