Financing - Summary of financing arrangements (Details) - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Repurchase Agreements [Abstract]
Current Face	$ 8,243,031,000
Carrying Value	$ 8,100,775,000	$ 6,329,796,000
Weighted Average Funding Cost	5.44%
Weighted Average Life (in years)	5 years 18 days
Cash pledged (i.e., restricted cash) under repurchase agreements	$ 7,800,000	10,600,000
Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	1,253,086,000
February 2029 Senior Unsecured Notes
Repurchase Agreements [Abstract]
Carrying Value	33,327,000
May 2029 Senior Unsecured Notes
Repurchase Agreements [Abstract]
Carrying Value	63,131,000
Securitized Residential Mortgage Loans \| Securitized Debt
Repurchase Agreements [Abstract]
Current Face	7,317,137,000
Carrying Value	$ 7,177,923,000	5,491,967,000
Weighted Average Funding Cost	5.39%
Weighted Average Life (in years)	5 years 5 months 1 day
Total Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	$ 826,394,000
Total Financing Arrangements \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	826,394,000
Carrying Value	$ 826,394,000	742,108,000
Weighted Average Funding Cost	5.27%
Weighted Average Life (in years)	2 months 12 days
Total Financing Arrangements \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 1,253,086,000
Non-Agency Loans
Repurchase Agreements [Abstract]
Current Face	29,817,000
Non-Agency Loans \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	29,817,000
Carrying Value	$ 29,817,000	7,615,000
Weighted Average Funding Cost	5.73%
Weighted Average Life (in years)	5 months 8 days
Non-Agency Loans \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 35,108,000
Non-Agency Loans \| Securitized Residential Mortgage Loans
Repurchase Agreements [Abstract]
Current Face	428,657,000
Non-Agency Loans \| Securitized Residential Mortgage Loans \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	428,657,000
Carrying Value	$ 428,657,000	370,913,000
Weighted Average Funding Cost	5.28%
Weighted Average Life (in years)	1 month 28 days
Non-Agency Loans \| Securitized Residential Mortgage Loans \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 641,399,000
Non-Agency Loans \| Securitized Residential Mortgage Loans \| Securitized Debt
Repurchase Agreements [Abstract]
Current Face	6,432,326,000
Carrying Value	$ 6,265,540,000	5,391,413,000
Weighted Average Funding Cost	5.37%
Weighted Average Life (in years)	5 years 8 months 23 days
Non-Agency Loans \| Counterparty One and Two
Repurchase Agreements [Abstract]
Line of credit facility, maximum borrowing capacity	$ 1,600,000,000
Maximum borrowing capacity committed by lender	50,000,000
Home Equity Loans
Repurchase Agreements [Abstract]
Current Face	58,951,000
Home Equity Loans \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	58,951,000
Carrying Value	$ 58,951,000	87,440,000
Weighted Average Funding Cost	6.27%
Weighted Average Life (in years)	5 months 19 days
Line of credit facility, maximum borrowing capacity	$ 50,000,000
Fair value of collateral pledged	69,700,000
Unpaid Principal Balance	66,800,000
Outstanding financing	$ 0
Advance rate, percentage of unpaid principal balance	87.50%
Home Equity Loans \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 142,339,000
Home Equity Loans \| Securitized Residential Mortgage Loans
Repurchase Agreements [Abstract]
Current Face	67,752,000
Notional balance	295,400,000
Home Equity Loans \| Securitized Residential Mortgage Loans \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	67,752,000
Carrying Value	$ 67,752,000	0
Weighted Average Funding Cost	4.67%
Weighted Average Life (in years)	1 month 9 days
Home Equity Loans \| Securitized Residential Mortgage Loans \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 84,064,000
Home Equity Loans \| Securitized Residential Mortgage Loans \| Securitized Debt
Repurchase Agreements [Abstract]
Current Face	784,881,000
Carrying Value	$ 817,889,000	0
Weighted Average Funding Cost	5.81%
Weighted Average Life (in years)	2 years 7 months 20 days
Re- and Non-Performing Loans \| Securitized Residential Mortgage Loans
Repurchase Agreements [Abstract]
Current Face	$ 27,264,000
Re- and Non-Performing Loans \| Securitized Residential Mortgage Loans \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	27,264,000
Carrying Value	$ 27,264,000	31,798,000
Weighted Average Funding Cost	5.89%
Weighted Average Life (in years)	25 days
Re- and Non-Performing Loans \| Securitized Residential Mortgage Loans \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 41,438,000
Re- and Non-Performing Loans \| Securitized Residential Mortgage Loans \| Securitized Debt
Repurchase Agreements [Abstract]
Current Face	99,930,000
Carrying Value	$ 94,494,000	100,554,000
Weighted Average Funding Cost	3.45%
Weighted Average Life (in years)	3 years 3 months 7 days
Agency-Eligible Loans
Repurchase Agreements [Abstract]
Current Face	$ 19,490,000
Agency-Eligible Loans \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	19,490,000
Carrying Value	$ 19,490,000	95,688,000
Weighted Average Funding Cost	5.43%
Weighted Average Life (in years)	10 months 13 days
Agency-Eligible Loans \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 21,149,000
Legacy WMC Commercial loans \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	27,436,000
Carrying Value	$ 27,436,000	47,222,000
Weighted Average Funding Cost	6.73%
Weighted Average Life (in years)	2 months 23 days
Legacy WMC Commercial loans \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 55,376,000
Non-Agency RMBS
Repurchase Agreements [Abstract]
Current Face	137,386,000
Non-Agency RMBS \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	137,386,000
Carrying Value	$ 137,386,000	78,978,000
Weighted Average Funding Cost	4.64%
Weighted Average Life (in years)	1 month 20 days
Non-Agency RMBS \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 173,891,000
Legacy WMC CMBS
Repurchase Agreements [Abstract]
Current Face	18,540,000
Unpaid Principal Balance	23,500,000	23,500,000
Legacy WMC CMBS \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	18,540,000
Carrying Value	$ 18,540,000	20,416,000
Weighted Average Funding Cost	5.29%
Weighted Average Life (in years)	1 month 28 days
Legacy WMC CMBS \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 42,538,000
Agency RMBS
Repurchase Agreements [Abstract]
Current Face	10,857,000
Agency RMBS \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	10,857,000
Carrying Value	$ 10,857,000	2,038,000
Weighted Average Funding Cost	4.32%
Weighted Average Life (in years)	2 months 12 days
Agency RMBS \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 15,465,000
Other assets
Repurchase Agreements [Abstract]
Current Face	244,000
Other assets \| Financing Arrangements
Repurchase Agreements [Abstract]
Current Face	244,000
Carrying Value	$ 244,000	0
Weighted Average Funding Cost	5.73%
Weighted Average Life (in years)	5 months 8 days
Other assets \| Financing Arrangements \| Asset Pledged as Collateral
Repurchase Agreements [Abstract]
Collateral Fair Value	$ 319,000
Senior Notes
Repurchase Agreements [Abstract]
Current Face	99,500,000
Carrying Value	$ 96,458,000	95,721,000
Weighted Average Funding Cost	10.61%
Weighted Average Life (in years)	3 years 3 months 29 days
Long-term debt, fair value	$ 101,700,000
February 2029 Senior Unsecured Notes
Repurchase Agreements [Abstract]
Current Face	$ 34,500,000
Carrying Value		33,028,000
Weighted Average Funding Cost	10.79%
Weighted Average Life (in years)	3 years 2 months 1 day
May 2029 Senior Unsecured Notes
Repurchase Agreements [Abstract]
Current Face	$ 65,000,000
Carrying Value		$ 62,693,000
Weighted Average Funding Cost	10.52%
Weighted Average Life (in years)	3 years 5 months 1 day
Interest Only \| Securitized Residential Mortgage Loans
Repurchase Agreements [Abstract]
Notional balance	$ 3,700,000,000

Assets Sold Under Agreements To Repurchase, Collateral Fair Value

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Assets Sold Under Agreements To Repurchase, Current Face

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Represents the weighted average funding cost for assets sold under agreements to repurchase.

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Assets Sold Under Agreements To Repurchase Weighted Average Life

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Debt Instrument, Interest Notional Balance

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Debt Instrument, Notional Balance

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Line Of Credit Facility, Advance Rate, Percentage Of Unpaid Principal Balance

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Line Of Credit Facility, Maximum Borrowing Capacity, Committed By Lender

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Repurchase Agreements

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Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

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Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount of 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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This is the result of the principal amount outstanding of total loans managed or securitized less securitized loans and loans that are in the process of being securitized.

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