Fair Value Measurement of Assets and Liabilities - Fair Value Measurements of Assets and Liabilities (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets	$ 21.4	$ 1.4
Contingent payments related to acquisitions	43.1	48.2
Total Liabilities	69.3	183.2
Fair Value Measurements at Reporting Date Using: Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets	21.4	1.4
Total Liabilities	26.2	135.0
Fair Value Measurements at Reporting Date Using: Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent payments related to acquisitions	43.1	48.2
Total Liabilities	43.1	48.2
Foreign Exchange Forward Contracts [Member] | Derivatives Designated as Hedges [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, current and long-term	15.9	0.5
Derivatives, current and long-term	12.1	48.5
Foreign Exchange Forward Contracts [Member] | Derivatives Not Designated as Hedges [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, current and long-term		0.9
Derivatives, current and long-term		3.2
Foreign Exchange Forward Contracts [Member] | Fair Value Measurements at Reporting Date Using: Significant Other Observable Inputs (Level 2) [Member] | Derivatives Designated as Hedges [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, current and long-term	15.9	0.5
Derivatives, current and long-term	12.1	48.5
Foreign Exchange Forward Contracts [Member] | Fair Value Measurements at Reporting Date Using: Significant Other Observable Inputs (Level 2) [Member] | Derivatives Not Designated as Hedges [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, current and long-term		0.9
Derivatives, current and long-term		3.2
Cross-currency Interest Rate Swaps [Member] | Derivatives Designated as Hedges [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, current and long-term	4.7
Derivatives, current and long-term	13.4	83.3
Cross-currency Interest Rate Swaps [Member] | Fair Value Measurements at Reporting Date Using: Significant Other Observable Inputs (Level 2) [Member] | Derivatives Designated as Hedges [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, current and long-term	4.7
Derivatives, current and long-term	13.4	$ 83.3
Interest Rate Swaps [Member] | Derivatives Designated as Hedges [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, current and long-term	0.8
Derivatives, current and long-term	0.7
Interest Rate Swaps [Member] | Fair Value Measurements at Reporting Date Using: Significant Other Observable Inputs (Level 2) [Member] | Derivatives Designated as Hedges [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives, current and long-term	0.8
Derivatives, current and long-term	$ 0.7