Consolidated Securitization Vehicles (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Book Value, net	$ 139,500	$ 141,500
Securitization Vehicles | Loans Receivable
Number of Loans	6	7
Principal Balance	157,579	164,180
Book Value, net	139,500	141,500
Securitization Vehicles | Loans Receivable | Risk Rating 1-3
Number of Loans	2	2
Principal Balance	50,000	47,000
Book Value, net	50,000	47,000
Securitization Vehicles | Loans Receivable | Risk Rating 4-5
Number of Loans	2	2
Principal Balance	89,500	92,500
Book Value, net	89,500	92,500
Securitization Vehicles | Loans Receivable | Risk Rating 6-8
Number of Loans	2	3
Principal Balance	18,079	24,680
Book Value, net		2,000
Securitization Vehicles | Senior Mortgages
Number of Loans	1	1
Principal Balance	62,500	62,500
Book Value, net	62,500	62,500
Securitization Vehicles | Senior Mortgages | Risk Rating 4-5
Number of Loans	1	1
Principal Balance	62,500	62,500
Book Value, net	62,500	62,500
Securitization Vehicles | Subordinated interests in mortgages
Number of Loans	5	6
Principal Balance	95,079	101,680
Book Value, net	77,000	79,000
Securitization Vehicles | Subordinated interests in mortgages | Risk Rating 1-3
Number of Loans	2	2
Principal Balance	50,000	47,000
Book Value, net	50,000	47,000
Securitization Vehicles | Subordinated interests in mortgages | Risk Rating 4-5
Number of Loans	1	1
Principal Balance	27,000	30,000
Book Value, net	27,000	30,000
Securitization Vehicles | Subordinated interests in mortgages | Risk Rating 6-8
Number of Loans	2	3
Principal Balance	18,079	24,680
Book Value, net		$ 2,000