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Mortgage Servicing - Schedule of Composition of Servicing UPB (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | --- | ---
Servicing Assets at Fair Value [Line Items] |  |  |
MSRs, at fair value | $ 2,547.4 | $ 2,466.3 | $ 2,272.2
Assets serviced | 178,100.0 | 170,300.0 |
UPB of loans transferred | 52,545.6 | 49,641.2 |
Owned MSRs |  |  |
Servicing Assets at Fair Value [Line Items] |  |  |
MSRs, at fair value | 1,956.1 | 1,869.6 |
Assets serviced | 137,800.0 | 129,800.0 |
MAV Transferred MSRs |  |  |
Servicing Assets at Fair Value [Line Items] |  |  |
MSRs, at fair value | 325.7 | 330.6 |
Assets serviced | $ 21,100.0 | $ 21,500.0 |

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