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Fair value measurements - Summary of assets measured on a recurring basis (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Securitized Debt |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | $ (5,491,967) | $ (4,711,623)
Transfers out of level 3 |  | 0
Purchases | 0 | 0
Issuances of Securitized Debt | (2,735,729) | (1,372,097)
Capital distributions | 0 | 0
Proceeds from sales or settlements | 0 | 0
Principal repayments | 1,236,013 | 657,092
Principal funding | 0 | 0
Total net gains/(losses) |  |
Other | 0 | 0
Ending Balance | (7,177,923) | (5,491,967)
Securitized Debt | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings | (23,561) | (30,310)
Securitized Debt | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings | 0 | 0
Securitized Debt | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings | (162,679) | (35,029)
Securitized Debt | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings | 0 | 0
Securitized Debt | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Change in unrealized appreciation/(depreciation) for level 3 assets/liabilities still held | (22,448) | (30,310)
Securitized Debt | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Change in unrealized appreciation/(depreciation) for level 3 assets/liabilities still held | (162,333) | (35,029)
Securitized Debt | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Change in unrealized appreciation/(depreciation) for level 3 assets/liabilities still held | 0 | 0
Other liabilities |  |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | (336) | (7)
Transfers out of level 3 |  | 0
Purchases | 0 | 0
Issuances of Securitized Debt | 0 | 0
Capital distributions | 0 | 0
Proceeds from sales or settlements | 1,190 | 1,379
Principal repayments | 0 | 0
Principal funding | 0 | 0
Total net gains/(losses) |  |
Other | 0 | 0
Ending Balance | 0 | (336)
Other liabilities | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings | 0 | 0
Other liabilities | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings | (1,190) | (1,379)
Other liabilities | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings | 336 | (329)
Other liabilities | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings | 0 | 0
Other liabilities | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Change in unrealized appreciation/(depreciation) for level 3 assets/liabilities still held | 0 | 0
Other liabilities | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Change in unrealized appreciation/(depreciation) for level 3 assets/liabilities still held | 0 | (336)
Other liabilities | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Change in unrealized appreciation/(depreciation) for level 3 assets/liabilities still held | 0 | 0
Residential Mortgage |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 6,416,066 | 5,675,135
Transfers out of level 3 | (1,600) | (1,629)
Purchases | 3,032,638 | 1,746,012
Issuances of Securitized Debt | 0 | 0
Capital distributions | 0 | 0
Proceeds from sales or settlements | (407,158) | (355,229)
Principal repayments | (1,039,354) | (710,639)
Principal funding | 17,691 | 2,070
Total net gains/(losses) |  |
Other | (9,728) | (3,098)
Ending Balance | 8,198,215 | 6,416,066
Residential Mortgage | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 2,459 | 14,839
Residential Mortgage | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | (4,785) | 6,352
Residential Mortgage | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 190,386 | 42,253
Residential Mortgage | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
Residential Mortgage | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 2,838 | 14,753
Residential Mortgage | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 185,549 | 41,011
Residential Mortgage | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 0 | 0
Legacy WMC Commercial loans |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 67,005 | 66,303
Transfers out of level 3 |  | 0
Purchases | 0 | 0
Issuances of Securitized Debt | 0 | 0
Capital distributions | 0 | 0
Proceeds from sales or settlements | 0 | 0
Principal repayments | 0 | 0
Principal funding | 0 | 0
Total net gains/(losses) |  |
Other | 0 | 0
Ending Balance | 55,376 | 67,005
Legacy WMC Commercial loans | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | (229) | 434
Legacy WMC Commercial loans | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
Legacy WMC Commercial loans | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | (11,400) | 268
Legacy WMC Commercial loans | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
Legacy WMC Commercial loans | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | (229) | 434
Legacy WMC Commercial loans | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | (11,400) | 268
Legacy WMC Commercial loans | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 0 | 0
Non-Agency RMBS |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 115,533 | 37,533
Transfers out of level 3 |  | 0
Purchases | 80,731 | 95,395
Issuances of Securitized Debt | 0 | 0
Capital distributions | 0 | 0
Proceeds from sales or settlements | 0 | (20,289)
Principal repayments | (10,668) | (1,847)
Principal funding | 0 | 0
Total net gains/(losses) |  |
Other | 0 | 0
Ending Balance | 191,546 | 115,533
Non-Agency RMBS | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | (2,835) | 17
Non-Agency RMBS | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | (87)
Non-Agency RMBS | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 8,785 | 4,811
Non-Agency RMBS | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
Non-Agency RMBS | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | (2,835) | 17
Non-Agency RMBS | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 8,785 | 4,811
Non-Agency RMBS | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 0 | 0
CMBS |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 0 | 5,796
Transfers out of level 3 | (5,800) | (5,796)
Purchases |  | 0
Issuances of Securitized Debt |  | 0
Capital distributions |  | 0
Proceeds from sales or settlements |  | 0
Principal repayments |  | 0
Principal funding |  | 0
Total net gains/(losses) |  |
Other |  | 0
Ending Balance |  | 0
CMBS | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings |  | 0
CMBS | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings |  | 0
CMBS | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings |  | 0
CMBS | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings |  | 0
CMBS | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations |  | 0
CMBS | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations |  | 0
CMBS | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations |  | 0
Legacy WMC Other Securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 0 | 1,156
Transfers out of level 3 |  | 0
Purchases |  | 0
Issuances of Securitized Debt |  | 0
Capital distributions |  | 0
Proceeds from sales or settlements |  | (762)
Principal repayments |  | 0
Principal funding |  | 0
Total net gains/(losses) |  |
Other |  | 0
Ending Balance |  | 0
Legacy WMC Other Securities | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings |  | (185)
Legacy WMC Other Securities | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings |  | (227)
Legacy WMC Other Securities | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings |  | 18
Legacy WMC Other Securities | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings |  | 0
Legacy WMC Other Securities | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations |  | 0
Legacy WMC Other Securities | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations |  | 0
Legacy WMC Other Securities | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations |  | 0
Other assets |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 204 | 1,172
Transfers out of level 3 |  | 0
Purchases | 0 | 0
Issuances of Securitized Debt | 0 | 0
Capital distributions | 0 | 0
Proceeds from sales or settlements | (1,098) | (2,739)
Principal repayments | 0 | 0
Principal funding | 0 | 0
Total net gains/(losses) |  |
Other | 0 | 0
Ending Balance | 0 | 204
Other assets | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
Other assets | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 1,098 | 2,739
Other assets | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | (204) | (968)
Other assets | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
Other assets | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 0 | 0
Other assets | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 0 | 204
Other assets | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 0 | 0
AG Arc |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 30,778 | 33,574
Transfers out of level 3 |  | 0
Purchases | 15,330 | 0
Issuances of Securitized Debt | 0 | 0
Capital distributions | (628) | (5,042)
Proceeds from sales or settlements | 0 | 0
Principal repayments | 0 | 0
Principal funding | 0 | 0
Total net gains/(losses) |  |
Other | 0 | 0
Ending Balance | 50,016 | 30,778
AG Arc | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
AG Arc | Net realized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
AG Arc | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 0 | 0
AG Arc | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Fair value, measurement with unobservable inputs reconciliation, recurring basis, asset, gain (loss) included in earnings | 4,536 | 2,246
AG Arc | Level 3 | Net premium and discount amortization |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 0 | 0
AG Arc | Level 3 | Net unrealized gain/(loss) |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | 0 | 0
AG Arc | Level 3 | Equity in earnings/(loss) from affiliates |  |
Total net gains/(losses) |  |
Unrealized gains/(losses) recorded in the consolidated statement of operations | $ 4,536 | $ 2,246

X
- Definition Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Asset, Distributions + References No definition available. + Details
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- Definition Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Other + References No definition available. + Details
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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Principal Funding + References No definition available. + Details
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- Definition Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Liability, Distributions + References No definition available. + Details
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- Definition Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Principal Funding + References No definition available. + Details
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- References No definition available. + Details
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- Definition Total Liability Gain (Loss) + References No definition available. + Details
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- Definition Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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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. + Details
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- Definition Amount of unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2G -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2G Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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