Supplemental Disclosure to Cash Flows - Summary of Supplemental Non-Cash and Other Cash Flow Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Cash Flow Elements [Abstract]
Cash paid for income taxes, net of refunds	$ 14,048	$ 6,759	$ 386
Non-cash transactions:
Contingent consideration related to business combinations	3,325	952	0
Property and equipment purchases in accounts payable	82	315	270
Purchase of assets under capital lease obligations	$ 134	$ 0	$ 0