Loan and Security Agreements (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Loan and Security Agreements [Line Items]
Unused line fee	$ 20,000	$ 40,000
Loan maximum defined, based on eligible receivable	85.00%
Maximum borrowing capacity	10,000,000
Additonal borrowing availability	5,000,000
Facility fee, percentage	1.00%
Monthly collateral fee	1,500
Monthly collertal fee (upon default)	3,000
Interest rate, stated percentage	6.00%
Commitment fee	100,000
Other issue costs	700,000
Facility fee amount	10,000
Prime rate [Member]
Loan and Security Agreements [Line Items]
Spread on variable rate	2.75%
LIBOR 90 day rate [Member]
Loan and Security Agreements [Line Items]
Spread on variable rate	5.25%
Prior to first anniversary [Member]
Loan and Security Agreements [Line Items]
Credit facility - early termination fee	3.00%
Prior to second anniversary [Member]
Loan and Security Agreements [Line Items]
Credit facility - early termination fee	2.00%
Prior to third anniversary [Member]
Loan and Security Agreements [Line Items]
Credit facility - early termination fee	1.00%
First amendment [Member]
Loan and Security Agreements [Line Items]
Facility fee, percentage	1.50%
Monthly collateral fee	2,500
Monthly collertal fee (upon default)	5,000
Amendment fee	$ 200,000
First amendment [Member] | Prior to first anniversary [Member]
Loan and Security Agreements [Line Items]
Credit facility - early termination fee	5.00%
First amendment [Member] | Prior to second anniversary [Member]
Loan and Security Agreements [Line Items]
Credit facility - early termination fee	3.00%
First amendment [Member] | Prior to third anniversary [Member]
Loan and Security Agreements [Line Items]
Credit facility - early termination fee	2.00%