Fair Value Measurements (Changes in Level 3 Liabilities) (Details) - SWAPS RELATED TO SALE OF CERTAIN VISA CLASS B COMMON SHARES - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||||
| Fair value liabilities beginning balance | $ 29.5 | $ 21.1 | $ 27.2 | $ 25.4 |
| Total (Gains) Losses: | ||||
| Included in Earnings | (0.2) | 15.4 | 5.4 | 16.6 |
| Purchases, Issues, Sales, and Settlements | ||||
| Settlements | (6.5) | (5.9) | (9.8) | (11.4) |
| Fair value liabilities ending balance | $ 22.8 | $ 30.6 | $ 22.8 | $ 30.6 |