Derivative Instruments and Hedging Activities - Gross Unrealized Losses from Derivative Instruments (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	$ 23.6	$ (32.8)
Amount of Gain / (Loss) Reclassified from AOCI	7.6	20.8
Cash Flow Hedges [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain / (Loss) Recognized in AOCI	23.6	(32.8)
Amount of Gain / (Loss) Reclassified from AOCI	7.6	20.8
Cash Flow Hedges [Member] | Foreign Exchange Forward Contracts [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain / (Loss) Recognized in AOCI	23.6	(32.8)
Amount of Gain / (Loss) Reclassified from AOCI	7.8	21.0
Cash Flow Hedges [Member] | Forward Starting Interest Rate Swaps [Member]
Derivative Instruments Gain Loss [Line Items]
Amount of Gain / (Loss) Reclassified from AOCI	$ (0.2)	$ (0.2)