Residential Whole Loans - Allowance for Credit Losses (Details) - Residential whole loans - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 9,705	$ 10,665
Current provision/(reversal)	(241)	145
Write-offs	(27)	(616)
Ending balance	9,437	10,194
Non-QM loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,725	2,125
Current provision/(reversal)	(317)	(197)
Write-offs	0	0
Ending balance	1,408	1,928
Loans	5,531,388		$ 5,346,693
Business purpose loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Loans	2,261,932		2,443,328
Business purpose loans \| Single-family rental loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	918	366
Current provision/(reversal)	(156)	614
Write-offs	0	0
Ending balance	762	980
Loans	1,196,609		1,235,346
Business purpose loans \| Single-family transitional loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	1,042	1,389
Current provision/(reversal)	114	(88)
Write-offs	0	(436)
Ending balance	1,156	865
Loans	658,713		718,345
Business purpose loans \| Single-family transitional loans \| Collateral Dependent Methodology
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Loans	3,800	11,000
Legacy RPL/NPL loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,020	6,785
Current provision/(reversal)	118	(184)
Write-offs	(27)	(180)
Ending balance	6,111	6,421
Loans	949,434		$ 979,016
Legacy RPL/NPL loans \| Collateral Dependent Methodology
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Loans	$ 26,700	$ 37,000

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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