Fixed Assets (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Furniture and fixtures	$ 40	$ 47
Laboratory equipment	508	508
Computer and communications equipment	261	261
Design and tooling	1,204	1,204
Property, Plant and Equipment, Gross, Total	2,013	2,020
Less accumulated depreciation and amortization	(1,982)	(1,941)
Total	$ 31	$ 79	[1]

[1] Derived from audited information