Stockholders' Equity - Common and Preferred Shares (Details 2) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Summary of the Company's stock option activity under its 2005 Plan
Shares, Options outstanding at December 31, 2011	1,002
Shares, Granted	774
Shares, Forfeited and expired	(548)
Shares, Options outstanding at June 30, 2012	1,228	1,002
Shares, Options exercisable at June 30, 2012	337
Shares, Options vested or expected to vest at June 30, 2012	815
Weighted Average Exercise Price, Options outstanding at December 31, 2011	$ 5.91
Weighted Average Exercise Price, Granted	$ 1.07
Weighted Average Exercise Price, Forfeited and expired	$ 7.35
Weighted Average Exercise Price, Options outstanding at June 30, 2012	$ 2.22	$ 5.91
Weighted Average Exercise Price, Options exercisable at June 30, 2012	$ 3.89
Weighted Average Exercise Price, Options vested or expected to vest at June 30, 2012	$ 2.62
Weighted Average Remaining Contractual Life, Options outstanding at December 31, 2011	9 years 4 months 6 days	9 years 2 months 19 days
Weighted Average Remaining Contractual Life, Options outstanding at June 30, 2012	9 years 4 months 6 days	9 years 2 months 19 days
Weighted Average Remaining Contractual Life, Options exercisable at June 30, 2012	8 years 7 months 6 days
Weighted Average Remaining Contractual Life, Options vested or expected to vest at June 30, 2012	9 years 2 months 9 days
Aggregate Intrinsic Value, Options vested or expected to vest at June 30, 2012