Property and Equipment - Schedule of Property and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Property, Plant and Equipment [Abstract]
Computer equipment and purchased software	$ 3,392	$ 3,595
Machinery and equipment	693	704
Furniture and fixtures	827	607
Leasehold improvements	1,297	938
Total	6,209	5,844
Less accumulated depreciation	(4,929)	(4,900)
Property and equipment, net	$ 1,280	$ 944