Fair Value Measurements - Summary of Changes in Fair Value of Level 3 Financial Instruments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Payment of contingent consideration in common stock		$ (322)
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Beginning Balance	$ 1,199	2,912
Payment of contingent consideration in cash		(240)
Payment of contingent consideration in common stock		(322)
Change in fair value	14	(1,151)
Reclassification of preferred stock warrant liabilities to additional paid-in capital in conjunction with the conversion of the convertible preferred stock into Class B common stock upon the closing of the Company’s IPO	(1,213)
Ending Balance		1,199
Stock Warrants | Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Beginning Balance	1,188	905
Change in fair value	25	283
Reclassification of preferred stock warrant liabilities to additional paid-in capital in conjunction with the conversion of the convertible preferred stock into Class B common stock upon the closing of the Company’s IPO	(1,213)
Ending Balance		1,188
Contingent Consideration | Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Beginning Balance	11	2,007
Payment of contingent consideration in cash		(240)
Payment of contingent consideration in common stock		(322)
Change in fair value	$ (11)	(1,434)
Ending Balance		$ 11