Income Taxes - Summary of Gross Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Gross unrecognized tax benefits at beginning of year	$ 1,158	$ 1,165
Gross increases in tax positions for current year	490	237
Settlements	(100)
Lapse of statute of limitations	(268)	(244)
Gross unrecognized tax benefits at end of year	$ 1,280	$ 1,158