5. Fixed assets (Details) - Fixed Asset Components (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Fixed Asset Components [Abstract]
Tooling, machinery and equipment	$ 12,066	$ 12,913
Furniture and office equipment	1,492	1,555
Computer software and equipment	5,986	5,546
Leasehold improvements	1,926	1,800
	21,470	21,814
Less: Accumulated depreciation and amortization	(18,989)	(18,925)
	2,481	2,889
Construction in-process	251	413
	$ 2,732	$ 3,302