Convertible Debt (Details) (USD $)	12 Months Ended				0 Months Ended	12 Months Ended		0 Months Ended	1 Months Ended			12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Aug. 25, 2009	Apr. 18, 2011 Rennes Foundation [Member]	Dec. 31, 2011 Rennes Foundation [Member]	Aug. 25, 2009 Rennes Foundation [Member]	Apr. 18, 2011 Whitebox VSC, Ltd and IAM Mini-Fund 14 Limited [Member]	Aug. 31, 2009 Whitebox VSC, Ltd and IAM Mini-Fund 14 Limited [Member] Debt_Instrument	Aug. 25, 2009 Whitebox VSC, Ltd and IAM Mini-Fund 14 Limited [Member]	Aug. 25, 2009 Whitebox VSC, Ltd [Member]	Dec. 31, 2010 IAM Mini-Fund 14 Limited [Member]	Aug. 25, 2009 IAM Mini-Fund 14 Limited [Member]
Schedule of Convertible Debt Instruments [Line Items]
Convertible debt, face amount							$ 5,000,000.0			$ 20,000,000	$ 19,000,000		$ 1,000,000
Convertible debt, conversion price							$ 16.66				$ 16.00		$ 16
Convertible debt, stated interest rate							0.00%				0.00%		0.00%
Convertible debt, imputed interest rate				1.75%			1.75%						1.75%
Interest expense recognized on convertible debt		21,000	328,000			21,000						328,000
Repayments of convertible debt	0	6,761,000	22,521,000		5,000,000.00			20,000,000
Convertible debt, payment for conversion spread					1,800,000			2,500,000.0
Number of convertible debt instruments									2
Stock issued to repay beneficial conversion feature on convertible debt								283,738
Convertible debt, carrying amount				24,200,000
Convertible debt, unamortized discount				$ 852,000