Balance Sheet Information - Summary of Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Payables And Accruals [Abstract]
Inventory receipts	$ 1,419	$ 2,191
Payroll, bonuses, and other employee benefits	1,245	859
Paid time off	1,164	1,067
Employee stock purchase plan	293	276
Warranties	244	270
Deferred liabilities	226	127
Professional fees	177	268
Real estate taxes	165	170
Restructuring	75	0
Sales tax	69	156
Other	674	515
Total	$ 5,751	$ 5,899