Income Taxes - Components of Income Tax Provision (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Current tax benefit (provision):      
State $ (2) $ (3) $ (3)
Foreign 95   (11)
Total 93 (3) (14)
Deferred tax benefit (provision):      
Federal 838 (31) (437)
State 52 12 (2)
Total 890 (19) (439)
Change in valuation allowance (890) 19 439
Total benefit (provision) for income taxes $ 93 $ (3) $ (14)