Finance Lease Receivables - Components of Finance Lease Receivables (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Financing Receivable, Allowance for Credit Losses	$ (2,572)	$ (2,257)	$ (848)
Finance Leases Financing Receivable [Member]
Total minimum lease receivable	76,763	99,808
Financing Receivable, Allowance for Credit Losses	(525)	(210)	(378)
Estimated unguaranteed residual values	7,508	6,048
Total Minimum Payments to be Received And Unguaranteed Residual Values	83,746	105,646
Unearned interest income	(4,771)	(6,190)
Unearned residuals	(1,319)	(1,160)
Unearned Interest Income and Residuals	(6,090)	(7,350)
Total	$ 77,656	$ 98,296