Investments - Schedule of Components of Real Estate Investments Held Under Direct Financing Leases (Details) - USD ($)
$ in Thousands
Jun. 30, 2015
Dec. 31, 2014
Investments in and Advances to Affiliates, Schedule of Investments [Abstract]    
Minimum lease payments receivable $ 14,210 $ 15,897
Estimated residual value of leased assets 43,789 55,858
Unearned income (13,617) (15,191)
Real estate assets under direct financing leases, net $ 44,382 $ 56,564