Schedule of Income subject to domestic and foreign taxation (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax [Abstract]
Income Before Tax, Domestic	$ 1,506.2	$ 1,596.8	$ 1,150.5
Income Before Tax, Foreign	133.9	153.2	110.1
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	1,640.1	1,750.0	1,260.6
Current Tax Expense (Benefit), Domestic	440.4	306.5	180.7
Current State and Local Tax Expense (Benefit)	(2.5)	12.7	2.6
Current Tax Expense (Benefit), Foreign	14.1	154.3	29.5
Income Tax (Benefit) - Current	452.0	473.5	212.8
Deferred Tax Expense (Benefit), Federal	(106.2)	42.7	54.0
Deferred State and Local Income Tax Expense (Benefit)	(1.5)	1.1	(2.2)
Deferred Tax Expense (Benefit), Foreign	12.0	(174.5)	15.0
Deferred Income Tax Expense (Benefit)	(95.7)	(130.7)	66.8
Income Tax Expense	$ 356.3	$ 342.8	$ 279.6