Financings - Commercial Mortgage Pass-Through Certificates (Details) - Secured Debt - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2019
RETL Trust
Debt Instrument [Line Items]
Principal Balance		$ 674,331,000
Fair Value		676,435,000
RETL Trust \| Class A
Debt Instrument [Line Items]
Principal Balance		$ 219,431,000
Coupon		2.90%
Fair Value		$ 219,567,000
RETL Trust \| Class B
Debt Instrument [Line Items]
Principal Balance		$ 101,200,000
Coupon		3.30%
Fair Value		$ 101,326,000
RETL Trust \| Class C
Debt Instrument [Line Items]
Principal Balance		$ 308,400,000
Coupon		3.80%
Fair Value		$ 309,171,000
RETL Trust \| Class HRR
Debt Instrument [Line Items]
Principal Balance		$ 45,300,000
Coupon		10.20%
Fair Value		$ 45,314,000
RETL Trust \| Class X-CP
Debt Instrument [Line Items]
Notional amount of nonderivative instruments		$ 308,400,000
Coupon		1.20%
Fair Value		$ 1,026,000
RETL Trust \| Class X-EXT
Debt Instrument [Line Items]
Notional amount of nonderivative instruments		$ 308,400,000
Coupon		0.00%
Fair Value		$ 31,000
Arroyo Trust
Debt Instrument [Line Items]
Principal Balance	$ 801,114,000
Fair Value	795,811,000
Carrying Value	801,109,000
Less: Unamortized Deferred Financing Costs	5,298,000
Arroyo Trust \| Class A-1
Debt Instrument [Line Items]
Principal Balance	$ 681,668,000
Coupon	3.30%
Carrying Value	$ 681,666,000
Arroyo Trust \| Class A-2
Debt Instrument [Line Items]
Principal Balance	$ 36,525,000
Coupon	3.50%
Carrying Value	$ 36,524,000
Arroyo Trust \| Class A-3
Debt Instrument [Line Items]
Principal Balance	$ 57,866,000
Coupon	3.80%
Carrying Value	$ 57,864,000
Arroyo Trust \| Class M-1
Debt Instrument [Line Items]
Principal Balance	$ 25,055,000
Coupon	4.80%
Carrying Value	$ 25,055,000
MRCD Trust
Debt Instrument [Line Items]
Principal Balance		245,000,000
Fair Value		208,547,000
MRCD Trust \| Class A
Debt Instrument [Line Items]
Principal Balance		$ 234,500,000
Coupon		4.30%
Fair Value		$ 198,104,000
MRCD Trust \| Class HRR
Debt Instrument [Line Items]
Principal Balance		$ 10,500,000
Coupon		12.00%
Fair Value		$ 10,443,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Debt Instrument, Premium, Coupon Rate

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