Balance Sheet Information - Summary of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Paid time off	$ 1,535	$ 1,247
Inventory receipts	1,476	2,471
Due to Nexgen Parties-working capital adjustment	892	0
Payroll, bonuses, and other employee benefits	789	1,539
Professional fees and contractors	694	223
Employee stock purchase plan	350	314
Warranties	304	304
Deferred revenues	208	1,262
Real estate taxes	167	181
Income and sales taxes	98	266
Executive deferred compensation	0	2,043
Other	448	361
Total	$ 6,961	$ 10,211