Balance Sheet Information - Summary of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Payables And Accruals [Abstract]
Paid time off	$ 1,320	$ 1,271
Inventory receipts	1,267	1,628
Payroll, bonuses, and other employee benefits	1,196	1,179
Income and sales taxes	478	381
Warranties	303	348
Employee stock purchase plan	257	280
Professional fees and contractors	227	305
Restructuring	208	237
Real estate taxes	150	161
Deferred revenues	105	65
Other	281	335
Total	$ 5,792	$ 6,190