Other Operating Income (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Other Operating Income (Details) - USD ($) $ in Millions	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Components of Other Operating Income [Line Items]
Total Other Operating Income	$ 56.4	$ 924.7	$ 107.1	$ 985.7
Loan Service Fees
Components of Other Operating Income [Line Items]
Total Other Operating Income	12.5	13.7	26.2	29.4
Banking Service Fees
Components of Other Operating Income [Line Items]
Total Other Operating Income	14.1	13.3	28.4	26.6
Bank Owned Life Insurance
Components of Other Operating Income [Line Items]
Total Other Operating Income	19.6	21.4	38.9	42.0
Other Income
Components of Other Operating Income [Line Items]
Total Other Operating Income	$ 10.2	876.3	$ 13.6	887.7
Other Income \| Visa Equity Securities
Components of Other Operating Income [Line Items]
Total Other Operating Income		$ 878.4		$ 878.4