Equity Incentive Plans and Warrants (Details 3) (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Company's stock option plans
Shares Outstanding, Beginning Balance	1,819	1,209	787
Shares, Granted	551	884	784
Shares, Exercised	(174)	(2)	(11)
Shares, Cancelled	(203)	(272)	(351)
Shares Outstanding, Ending Balance	1,993	1,819	1,209
Shares Exercisable	715	600
Weighted average exercise price per share, Beginning Balance	$ 3.07	$ 5.56	$ 15.75
Weighted Average Exercise Price per share, Granted	$ 4.08	$ 2.20	$ 2.90
Weighted average exercise Price per Share, exercised	$ 2.86	$ 0.72	$ 1.37
Weighted average exercise price per share, Cancelled	$ 3.12	$ 11.30	$ 22.62
Weighted average exercise price per share, Ending Balance	$ 3.36	$ 3.07	$ 5.56
Weighted average remaining contractual term, Outstanding, Ending Balance	8 years 4 months 24 days
Aggregate intrinsic value, Outstanding, Ending Balance	$ 257,000
Weighted Average Exercise Price per Share	$ 3.76
Weighted Average Remaining Contractual Term	7 years 8 months 12 days
Aggregate intrinsic value of options exercisable	$ 81,000	$ 8,000