Other Financing Liabilities, at Fair Value - Schedule of Activity Related to Financing Liability - MSRs Pledged (Details) - Financing Liability Mortgage Servicing Rights Pledged [Member] - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
|
| Servicing Asset at Fair Value, Amount [Roll Forward] | ||
| Beginning balance | $ 846.9 | $ 894.4 |
| MSR transfers | 6.7 | 7.0 |
| Changes in fair value due to inputs and assumptions | (1.0) | 19.8 |
| Realization of expected cash flows | (17.0) | (19.9) |
| Total fair value (gain) loss | (18.0) | (0.1) |
| Ending balance | 835.5 | 901.3 |
| Derecognition of financing liability | 0.0 | 0.0 |
| MSR Asset Vehicle LLC | ||
| Servicing Asset at Fair Value, Amount [Roll Forward] | ||
| MSR transfers | 0.0 | 0.2 |
| Other MSR Capital Partners | ||
| Servicing Asset at Fair Value, Amount [Roll Forward] | ||
| MSR transfers | $ 6.7 | $ 6.8 |