Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Residential (Details) $ in Thousands	1 Months Ended	12 Months Ended
Residential (Details) $ in Thousands	May 31, 2019 USD ($)	Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan	Sep. 30, 2019 USD ($)
Variable Interest Entity [Line Items]
Repurchase agreements		$ 2,824,801	$ 2,818,837
Principal amount of delinquent loans		19,233
Principal balance		$ 2,676,231
Residential Whole Loans
Variable Interest Entity [Line Items]
Number of Loans \| loan		3,529	2,782
Fair value		$ 1,200,566	$ 1,041,885
Principal balance		1,325,443	1,023,524
Residential Bridge Loans
Variable Interest Entity [Line Items]
Fair value		$ 33,269	211,999
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure \| Residential Whole Loans
Variable Interest Entity [Line Items]
Number of Loans \| loan		9
Variable Interest Entity, Primary Beneficiary, Aggregated Disclosure \| Residential Bridge Loans
Variable Interest Entity [Line Items]
Number of Loans \| loan		68
VIE \| Residential Whole Loans
Variable Interest Entity [Line Items]
Repurchase agreements		$ 209,900	$ 618,700
Number of Loans \| loan		3,520
Mortgage loans on real estate, number of loans		12	0
Principal amount of delinquent loans		$ 7,100
Mortgage loans on real estate, number of loans, nonperforming, percentage		0.50%
VIE \| Residential Bridge Loans
Variable Interest Entity [Line Items]
Repurchase agreements		$ 32,100	$ 207,500
Number of Loans \| loan		76	520
Mortgage loans on real estate, number of loans			3
Principal amount of delinquent loans			$ 1,100
Mortgage loans on real estate, number of loans, nonperforming, percentage		32.60%	2.30%
Principal amount at fair value of delinquent loans		$ 12,100
Principal balance		$ 37,196	$ 222,257
Original LTV, collateral dependent		72.10%	70.00%
Other Real Estate, Foreclosed Assets, and Repossessed Assets		$ 3,300
RCR Trust \| Residential Whole Loans
Variable Interest Entity [Line Items]
Repurchase agreements		164,300	$ 250,400
RNR Trust \| Residential Whole Loans
Variable Interest Entity [Line Items]
Repurchase agreements		8,100	15,100
Arroyo Mortgage Trust 2019-2 \| Residential Whole Loans
Variable Interest Entity [Line Items]
Repurchase agreements		919,000		$ 919,000
RBR Trust \| Residential Whole Loans
Variable Interest Entity [Line Items]
Repurchase agreements		91,700
Estimated Fair Value \| Residential Whole Loans
Variable Interest Entity [Line Items]
Fair value		1,375,860	1,041,885
Estimated Fair Value \| Residential Bridge Loans
Variable Interest Entity [Line Items]
Fair value		33,269	$ 211,999
Estimated Fair Value \| VIE \| Residential Whole Loans
Variable Interest Entity [Line Items]
Fair value		$ 6,700
Estimated Fair Value \| VIE \| Residential Bridge Loans
Variable Interest Entity [Line Items]
Mortgage loans on real estate, number of loans		27	9
Principal amount of delinquent loans			$ 4,000
Fair value		$ 11,400	$ 3,800
Arroyo Trust \| Arroyo Mortgage Trust 2019-2 \| Residential Whole Loans
Variable Interest Entity [Line Items]
Transfer of residential mortgage-backed securitization	$ 945,500