Residential Whole Loans and Bridge Loans - Aging of Delinquent Loans (Details) $ in Thousands	6 Months Ended
Jun. 30, 2022 USD ($) loan
Residential Whole-Loans
Variable Interest Entity [Line Items]
No of Loans \| loan	3,102
Principal	$ 1,239,970
Fair value	$ 1,195,853
Bridge loans
Variable Interest Entity [Line Items]
No of Loans \| loan	7
Principal	$ 5,585
Fair value	$ 5,095
Non-QM Loans
Variable Interest Entity [Line Items]
Number of loans in forbearance \| loan	1
Current \| Residential Whole-Loans
Variable Interest Entity [Line Items]
No of Loans \| loan	3,073
Principal	$ 1,226,815
Fair value	$ 1,183,917
Current \| Bridge loans
Variable Interest Entity [Line Items]
No of Loans \| loan	0
Principal	$ 0
Fair value	$ 0
1-30 days \| Residential Whole-Loans
Variable Interest Entity [Line Items]
No of Loans \| loan	8
Principal	$ 2,213
Fair value	$ 2,142
1-30 days \| Bridge loans
Variable Interest Entity [Line Items]
No of Loans \| loan	0
Principal	$ 0
Fair value	$ 0
31-60 days \| Residential Whole-Loans
Variable Interest Entity [Line Items]
No of Loans \| loan	1
Principal	$ 359
Fair value	$ 361
31-60 days \| Bridge loans
Variable Interest Entity [Line Items]
No of Loans \| loan	1
Principal	$ 849
Fair value	$ 832
61-90 days \| Residential Whole-Loans
Variable Interest Entity [Line Items]
No of Loans \| loan	0
Principal	$ 0
Fair value	$ 0
61-90 days \| Bridge loans
Variable Interest Entity [Line Items]
No of Loans \| loan	0
Principal	$ 0
Fair value	$ 0
90+ days \| Residential Whole-Loans
Variable Interest Entity [Line Items]
No of Loans \| loan	20
Principal	$ 10,583
Fair value	$ 9,433
90+ days \| Bridge loans
Variable Interest Entity [Line Items]
No of Loans \| loan	6
Principal	$ 4,736
Fair value	$ 4,263

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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