Accrued Liabilities - Summary of Accrued Warranty Obligations (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Payables And Accruals [Abstract]
Beginning balance	$ 2,321	$ 1,470
Warranty liabilities assumed from acquisition		450
Amortization of fair value adjustment of warranty liabilities acquired through acquisitions	(57)	(12)
Reduction of warranty liabilities assumed in connection with acquisitions	(384)	(174)
Warranty expense	722	912
Warranty charges	(607)	(239)
Ending balance	$ 1,995	$ 2,407