Income Taxes (Schedule of Composition of Income Tax Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
Federal	$ 3,017.9	$ 2,153.6	$ 938.5
Foreign	613.0	547.7	466.0
State	24.3	45.5	(28.4)
Total current tax expense	3,655.2	2,746.8	1,376.1
Deferred:
Federal	(2,369.0)	(1,992.4)	(977.5)
Foreign	34.2	(78.2)	174.6
State	(6.2)	(114.6)	0.6
Total deferred tax benefit	(2,341.0)	(2,185.2)	(802.3)
Income taxes	1,314.2	561.6	573.8
Current federal tax expense, utilization of net operating loss carryforward	$ 69.3	$ 189.5	$ 64.7