Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Net Deferred income tax assets:
Depreciation and amortization	$ 917	$ 1,055
Accrued expenses and reserves	1,771	1,796
Net operating loss carryforwards	20,509	20,768
Capital loss carryforwards	290	345
Research and development credit carryforwards	2,535	2,535
Stock-based compensation	425	305
Gross deferred tax assets	26,447	26,804
Less: valuation allowance	(24,102)	(24,192)
Net	$ 2,345	$ 2,612