Commitments and Contingencies - Summary of Rent Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]
Gross rent expense	$ 7,677	$ 7,023	$ 5,570
Sublease income	254	45	45
Net rent expense	$ 7,423	$ 6,978	$ 5,525