Schedule IV - Mortgage Loans on Real Estate (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
Mortgage Loans on Real Estate [Line Items]
Prior Liens	$ 1,266,259
Face amount of Mortgages	2,321,194
Mortgage loans on real estate, carrying amount	2,314,109
Provision for Loan and Lease Losses	(3,700)
Total Mortgages after Provision for Loan Losses	2,310,409
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	0
Aggregate cost for Federal income tax purposes	2,300,000
First mortgage loan
Mortgage Loans on Real Estate [Line Items]
Prior Liens	0
Face amount of Mortgages	2,033,866
Mortgage loans on real estate, carrying amount	2,027,976
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	0
Subordinated Mortgages
Mortgage Loans on Real Estate [Line Items]
Prior Liens	1,266,259
Face amount of Mortgages	287,328
Mortgage loans on real estate, carrying amount	286,133
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Hotel | First Mortgage 9.39%
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	9.39%
Prior Liens	$ 0
Face amount of Mortgages	107,887
Mortgage loans on real estate, carrying amount	107,472
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Hotel | First Mortgage 10.00%
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	10.00%
Prior Liens	$ 0
Face amount of Mortgages	104,000
Mortgage loans on real estate, carrying amount	103,865
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Hotel | First Mortgage 5.28%
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	5.28%
Prior Liens	$ 0
Face amount of Mortgages	73,023
Mortgage loans on real estate, carrying amount	72,933
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Hotel | First Mortgage 5.00%
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	5.00%
Prior Liens	$ 0
Face amount of Mortgages	97,500
Mortgage loans on real estate, carrying amount	96,892
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Hotel | First Mortgage 5.50%
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	5.50%
Prior Liens	$ 0
Face amount of Mortgages	77,541
Mortgage loans on real estate, carrying amount	77,240
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Hotel | Subordinated mortgages individually more than 3%
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	6.28%
Prior Liens	$ 0
Face amount of Mortgages	75,000
Mortgage loans on real estate, carrying amount	74,908
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Multi-family | First Mortgage 2.87%
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	2.87%
Prior Liens	$ 0
Face amount of Mortgages	120,000
Mortgage loans on real estate, carrying amount	120,000
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	0
Condo, Hotel, Industrial, Land, Mobile Home Park, Mixed Use Multi-family, Other Commercial, Retail | First mortgages individually less than 3%
Mortgage Loans on Real Estate [Line Items]
Prior Liens	0
Face amount of Mortgages	1,453,915
Mortgage loans on real estate, carrying amount	1,449,574
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Condo, Hotel, Industrial, Land, Mobile Home Park, Mixed Use Multi-family, Other Commercial, Retail | First mortgages individually less than 3% | Minimum
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	4.00%
Condo, Hotel, Industrial, Land, Mobile Home Park, Mixed Use Multi-family, Other Commercial, Retail | First mortgages individually less than 3% | Maximum
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	11.25%
Hotel, Industrial, Land, Mobile Home Park, Mixed Use, Multi-family, Office, Other Commercial, Retail | Subordinated mortgages individually less than 3%
Mortgage Loans on Real Estate [Line Items]
Prior Liens	$ 1,266,259
Face amount of Mortgages	212,328
Mortgage loans on real estate, carrying amount	211,225
Principal Amount of Mortgages Subject to Delinquent Principal or Interest	$ 0
Hotel, Industrial, Land, Mobile Home Park, Mixed Use, Multi-family, Office, Other Commercial, Retail | Subordinated mortgages individually less than 3% | Minimum
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	6.04%
Hotel, Industrial, Land, Mobile Home Park, Mixed Use, Multi-family, Office, Other Commercial, Retail | Subordinated mortgages individually less than 3% | Maximum
Mortgage Loans on Real Estate [Line Items]
Mortgage Loans on Real Estate, Interest Rate	19.00%