Fair Value - Summary of Assets Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Assets measured at fair value
Cash and cash equivalents	$ 52,893	$ 34,766	$ 44,344	$ 10,014
Restricted cash	0	250
Total Assets measured at fair value	52,893	35,016
Liabilities measured at fair value
Contingent consideration	24,300
Total liabilities measured at fair value	24,300
Fair Value, Inputs, Level 1 [Member]
Assets measured at fair value
Cash and cash equivalents	52,893	34,766
Restricted cash		250
Total Assets measured at fair value	52,893	$ 35,016
Fair Value, Inputs, Level 3 [Member]
Liabilities measured at fair value
Contingent consideration	24,300
Total liabilities measured at fair value	$ 24,300