Short-Term Borrowings and Long-Term Debt (Details) (USD $)				1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Level 3	Feb. 29, 2012 2011 Loan Agreement	Dec. 31, 2013 2011 Loan Agreement	Dec. 31, 2013 2013 Loan Agreement item	Dec. 31, 2013 2013 Loan Agreement item	Dec. 31, 2013 2013 Loan Agreement Level 3	Dec. 31, 2013 2013 Loan Agreement Maximum [Member]	Dec. 31, 2013 2013 Loan Agreement Maximum [Member] Level 3
Short-Term Borrowings and Long-Term Debt
Maximum amount of loan					$ 3,000,000	$ 25,000,000	$ 25,000,000
Fixed interest rate (as a percent)						8.50%	8.50%
Long-term portion, gross of debt discount	15,000,000				300,000	15,000,000	15,000,000
Variable interest rate base, SVB prime rate					SVB prime
Percentage points added to the reference rate					2.50%
SVB prime rate (as a percent)					4.00%
Amount borrowed				1,000,000		15,000,000
Amount available for borrowing									10,000,000
Period for repayment of debt				2 years 6 months
Less debt discount	826,000					800,000	800,000
Number of equal monthly installments for repayment of debt						33	33
Debt facility fee						100,000	100,000
Contingent exit fee payable						400,000	400,000
Fair value of contingent payment							300,000
Contingent success fee payable			264,000					300,000		400,000
Period of trigger event within which success fee is payable							6 months
Period of effectiveness of trigger event from closing of loan							5 years
Remaining future minimum payments of principal due
2014	299,000
2015	4,035,000
2016	5,443,000
2017	5,522,000
Total principal obligation	15,299,000
Less short-term portion	(299,000)	(398,000)
Long-term portion, gross of debt discount	15,000,000				300,000	15,000,000	15,000,000
Less debt discount	(826,000)					(800,000)	(800,000)
Long term portion, net of debt discount	$ 14,174,000	$ 299,000