Other Assets (Prepaid Expenses and Other Current Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Income tax receivable	$ 173.8	$ 170.7
Prepaid expenses	85.3	77.7
Inventories	72.2	59.1
Other non-trade receivables	32.2	32.2
Reinsurance receivable	31.0	34.1
Prepaid fees for cloud-based hosting arrangements, current	12.9	11.8
Other current assets	3.0	6.7
Total	$ 410.4	$ 392.3