Income Taxes (Schedule of Composition of Income Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal	$ 567.6	$ 280.2	$ 169.6
Foreign	650.4	299.8	106.8
State	(47.3)	(14.4)	4.7
Total current tax expense	1,170.7	565.6	281.1
Deferred:
Federal	(97.4)	141.3	(3.7)
Foreign	(16.6)	(24.1)	248.7
State	(20.5)	(54.8)	3.4
Total deferred tax (benefit) expense	(134.5)	62.4	248.4
Income taxes	1,036.2	628.0	529.5
Current federal tax expense, utilization of net operating loss carryforward	$ 144.4
Current federal tax expense, effect of 2017 Tax Act		$ 153.1	201.5
Deferred federal income tax benefit, effect of 2017 Tax Act			$ 26.2