Fair Value - Summary of Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Assets measured at fair value
Cash and cash equivalents	$ 42,518	$ 38,449	$ 52,893	$ 34,766
Restricted cash	10,353
Total	52,871	38,449
Liabilities measured at fair value
Contingent consideration	25,200	23,500
Total liabilities measured at fair value	25,200	23,500
Fair Value, Inputs, Level 1 [Member]
Assets measured at fair value
Cash and cash equivalents	42,518	38,449
Restricted cash	10,353
Total	52,871	38,449
Fair Value, Inputs, Level 3 [Member]
Liabilities measured at fair value
Contingent consideration	25,200	23,500
Total liabilities measured at fair value	$ 25,200	$ 23,500