Balance Sheet Information - Summary of Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Payables And Accruals [Abstract]
Payroll, bonuses, and other employee benefits	$ 2,634	$ 859
Inventory receipts	1,570	2,191
Paid time off	1,120	1,067
Warranties	274	270
Deferred liabilities	197	127
Professional fees	158	268
Real estate taxes	131	170
Employee stock purchase plan	115	276
Restructuring	56	0
Sales tax	1	156
Other	321	515
Total	$ 6,577	$ 5,899