Share-Based Compensation Plans - Total Compensation Expense for Share-Based Compensation Arrangements to Employees (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	$ 119.4	$ 118.2	$ 125.2
Tax Benefits Recognized	29.3	29.9	31.4
Restricted Stock Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	91.4	95.7	96.4
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-Based Compensation Expense	$ 28.0	$ 22.5	$ 28.8