Direct Financing Lease Receivables (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Credit risk profile by creditworthiness category of direct financing lease receivables, Total	$ 408,516	$ 428,142
Very low risk to low risk [Member]
Financing Receivable, Recorded Investment [Line Items]
Credit risk profile by creditworthiness category of direct financing lease receivables, Total	156,596	193,123
Moderate risk [Member]
Financing Receivable, Recorded Investment [Line Items]
Credit risk profile by creditworthiness category of direct financing lease receivables, Total	184,990	177,400
Moderately high to High risk [Member]
Financing Receivable, Recorded Investment [Line Items]
Credit risk profile by creditworthiness category of direct financing lease receivables, Total	$ 66,930	$ 57,619