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Summary of Significant Accounting Policies - Residential Whole Loans (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2026 | Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
LTV ratio (as a percent) | 80.00% |
Residential whole loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
LTV ratio (as a percent) | 64.00% | 64.00%
Residential whole loans | Business purpose loans |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
LTV ratio (as a percent) | 70.00% | 66.00%
Residential whole loans | Business purpose loans | Multifamily Properties |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Threshold balance (below) | $ 10 |

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- Definition The LTV of which the Company has assessed its residential whole loans at carrying value will have a higher likelihood of default than newly originated mortgage loans + References No definition available. + Details
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