Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
U.S. federal income taxes (including foreign withholding taxes):
Current federal income taxes	$ 168.0	$ 105.4	$ (52.6)
Deferred federal income taxes	(34.9)	13.2	(12.0)
Total federal income taxes	133.1	118.6	(64.6)
State and local income taxes:
Current state and local income taxes	40.4	27.4	(3.7)
Deferred state and local income taxes	(5.3)	(0.9)	0.5
Total state and local income taxes	35.1	26.5	(3.2)
Foreign income taxes:
Current foreign income taxes	137.0	127.2	110.7
Deferred foreign income taxes	13.2	(20.5)	(34.9)
Total foreign income taxes	150.2	106.7	75.8
Provision for income taxes	$ 318.4	$ 251.8	$ 8.0