Residential Whole Loans - Allowance for Credit Losses (Details) - Residential whole loans - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2026	Mar. 31, 2026	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 9,437	$ 9,705	$ 10,194	$ 10,665
Current provision/(reversal)	(62)	(242)	791	145
Write-offs	18	(26)	(1,036)	(616)
Ending balance	9,393	9,437	9,949	10,194
Non-QM loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	5,672,020				$ 5,346,693
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,408	1,725	1,928	2,125
Current provision/(reversal)	(116)	(317)	87	(197)
Write-offs	0	0	0	0
Ending balance	1,292	1,408	2,015	1,928
Business purpose loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	2,131,029				2,443,328
Business purpose loans \| Single-family rental loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	1,154,384				1,235,346
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	762	918	980	366
Current provision/(reversal)	158	(156)	(43)	614
Write-offs	0	0	0	0
Ending balance	920	762	937	980
Business purpose loans \| Single-family transitional loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	655,763				718,345
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,156	1,042	865	1,389
Current provision/(reversal)	386	114	669	(88)
Write-offs	0	0	(1,022)	(436)
Ending balance	1,542	1,156	512	865
Business purpose loans \| Single-family transitional loans \| Collateral Dependent Methodology
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	3,800		5,200
Seasoned RPL/NPL loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	925,157				$ 979,016
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,111	6,020	6,421	6,785
Current provision/(reversal)	(490)	117	78	(184)
Write-offs	18	(26)	(14)	(180)
Ending balance	5,639	$ 6,111	6,485	$ 6,421
Seasoned RPL/NPL loans \| Collateral Dependent Methodology
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans	$ 25,000		$ 31,800

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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