Net Investment in Direct Finance Leases (Details) (USD $)	Mar. 31, 2013		Dec. 31, 2012
Net investment in direct financing leases [Abstract]
Unearned income	$ (30,138,000)	[1]	$ (31,445,000)	[1]
Net investment in finance leases	85,980,000		85,554,000
Unguaranteed residual value	13,000,000		9,100,000
Executory costs	0		0
Unamortized initial direct costs	0		0
Gross finance lease receivables based on internal customer credit ratings [Abstract]
Gross finance lease receivables	116,118,000	[2]	116,999,000	[2]
Contractual maturities of gross finance lease receivables [Abstract]
2014	19,007,000
2015	22,810,000
2016	16,503,000
2017	17,705,000
2018	10,788,000
2019 and thereafter	29,305,000
Tier 1 [Member]
Gross finance lease receivables based on internal customer credit ratings [Abstract]
Gross finance lease receivables	98,443,000		98,611,000
Tier 2 [Member]
Gross finance lease receivables based on internal customer credit ratings [Abstract]
Gross finance lease receivables	17,675,000		18,388,000
Tier 3 [Member]
Gross finance lease receivables based on internal customer credit ratings [Abstract]
Gross finance lease receivables	$ 0		$ 0

[1] The difference between the gross finance lease receivable and the cost of the equipment or carrying amount at the lease inception is recorded as unearned income. Unearned income together with initial direct costs, are amortized to income over the lease term so as to produce a constant periodic rate of return. There were no unamortized initial direct costs as of March 31, 2013 and December 31, 2012.

[2] At the inception of the lease, the Company records the total minimum lease payments, executory costs, if any, and unguaranteed residual value as gross finance lease receivables. The gross finance lease receivable is reduced as customer payments are received. Approximately $13.0 million and $9.1 million of unguaranteed residual value at March 31, 2013 and December 31, 2012, respectively, were included in gross finance lease receivables. There were no executory costs included in gross finance lease receivables as of March 31, 2013 and December 31, 2012.