Goodwill and Other Intangible Assets - Schedule of Activity in Goodwill and Intangible Assets, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Intangible assets, net
Balance, beginning of period	$ 40,887	$ 41,783	$ 44,633
Acquisition	0	2,400	1,075
Amortization expense	(2,460)	(3,296)	(3,925)
Balance, end of period	38,427	40,887	41,783
Goodwill
Balance, beginning of period	6,701	5,260	5,260
Acquisition	0	1,441	0
Acquisition related adjustments	87	0	0
Balance, end of period	$ 6,788	$ 6,701	$ 5,260