Derivative Instruments and Hedging Activities - Net Investment Hedge Gains (Losses) Recognized on Condensed Consolidated Statements of Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in AOCI	$ 51.6	$ (98.3)
Euro Notes [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in AOCI	38.3	(75.7)
Swiss Notes [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in AOCI	10.0
Cross-currency Interest Rate Swaps [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain (Loss) Recognized in AOCI	$ 3.3	$ (22.6)