Income Taxes - Summary of Reconciliation of Unrecognized Tax Benefits (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Income Tax Disclosure [Abstract]    
Beginning balance $ 935 $ 215
Increases in tax positions for prior years 48 40
Decreases in tax positions for prior years   (18)
Settlements 0 698
Ending balance $ 983 $ 935