Note 4 - Property and Equipment (Details) - Property and Equipment (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Property and equipment at cost	$ 9,786	$ 9,840
Less: accumulated depreciation	(8,162)	(8,040)
Property and equipment, net	1,624	1,800
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	5,888	5,963
Tooling [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	2,598	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	537	462
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	629	633
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	$ 2	$ 50