Note 4 - Property and Equipment (Details) - Property and Equipment (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property and equipment at cost	$ 8,994	$ 9,840
Less: accumulated depreciation	(7,528)	(8,040)
Property and equipment, net	1,466	1,800
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	5,101	5,963
Tooling [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	2,576	2,600
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	132	132
Software and Software Development Costs [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	541	462
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	633	633
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	$ 11	$ 50