Balance Sheet Information - Summary of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Inventory receipts	$ 1,626	$ 2,471
Paid time off	1,338	1,247
Payroll, bonuses, and other employee benefits	991	1,539
Due to Nexgen Parties - working capital adjustment	840	0
Professional fees and contractors	403	223
Warranties	381	304
Deferred revenues	218	1,262
Real estate taxes	121	181
Income and sales taxes	157	266
Employee stock purchase plan	97	314
Executive deferred compensation	0	2,043
Other	258	361
Total	$ 6,430	$ 10,211