Goodwill and Other Intangibles (Other Intangible Assets and Capitalized Software) (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Other Intangible Assets
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 130.4	$ 135.0
Less: Accumulated Amortization	66.0	63.4
Net Book Value	64.4	71.6
Computer Software
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4,068.3	3,781.7
Less: Accumulated Amortization	2,043.7	1,754.2
Net Book Value	$ 2,024.6	$ 2,027.5