Goodwill and Intangible Assets - Components of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]
Beginning balance	$ 39,870	$ 20,335
Additions through acquisitions	72,528	19,952
Measurement period adjustments	27	(417)
Ending balance	$ 112,425	$ 39,870