Commercial Loans - Components of the carrying value of the commercial real estate loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Commercial Mezzanine Loan
Variable Interest Entity [Line Items]
Principal balance	$ 279,425	$ 50,000
Unamortized premium	0	0
Financing Receivables Unamortized Discount	(294)	(205)
Amortized cost	279,131	49,795
Gross unrealized gains	294	205
Gross unrealized losses	0	0
Fair value	279,425	50,000
CMSC Trust
Variable Interest Entity [Line Items]
Principal balance	24,048	24,456
Unamortized premium	0	0
Financing Receivables Unamortized Discount	0	0
Amortized cost	24,048	24,456
Gross unrealized gains	9	0
Gross unrealized losses	0	(14)
Fair value	24,057	24,442
RETL Trust
Variable Interest Entity [Line Items]
Principal balance	674,331	988,609
Unamortized premium	1,836	431
Financing Receivables Unamortized Discount	0	0
Amortized cost	676,167	989,040
Gross unrealized gains	269	29
Gross unrealized losses	0	0
Fair value	676,436	989,069
MRCD Trust
Variable Interest Entity [Line Items]
Principal balance	245,000	0
Unamortized premium	0	0
Financing Receivables Unamortized Discount	(35,119)	0
Amortized cost	209,881	0
Gross unrealized gains		0
Gross unrealized losses	(1,334)	0
Fair value	208,547	0
RSBC Trust
Variable Interest Entity [Line Items]
Principal balance	90,788	166,432
Unamortized premium	0	0
Financing Receivables Unamortized Discount	(215)	(736)
Amortized cost	90,573	165,696
Gross unrealized gains	215	427
Gross unrealized losses	0	0
Fair value	$ 90,788	$ 166,123

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 210
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