Financial Instruments and Fair Value - Summary of Fair Value Information (Details) - Recurring - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other noncurrent assets/(liabilities) - cross currency interest rate contracts designated as net investment hedges	$ 0.0	$ 0.0
Long-term debt - senior notes	0.0	0.0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other noncurrent assets/(liabilities) - cross currency interest rate contracts designated as net investment hedges	22.8	(7.4)
Long-term debt - senior notes	(2,120.0)	(2,005.0)
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other noncurrent assets/(liabilities) - cross currency interest rate contracts designated as net investment hedges	0.0	0.0
Long-term debt - senior notes	0.0	0.0
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other noncurrent assets/(liabilities) - cross currency interest rate contracts designated as net investment hedges	22.8	(7.4)
Long-term debt - senior notes	(2,000.0)	(2,000.0)
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other noncurrent assets/(liabilities) - cross currency interest rate contracts designated as net investment hedges	22.8	(7.4)
Long-term debt - senior notes	(2,120.0)	(2,005.0)
Other current liabilities - contingent consideration | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration		0.0
Other current liabilities - contingent consideration | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration		0.0
Other current liabilities - contingent consideration | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration		(5.1)
Other current liabilities - contingent consideration | Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration		(5.1)
Other current liabilities - contingent consideration | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration		(5.1)
Other noncurrent liabilities - contingent consideration | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	0.0	0.0
Other noncurrent liabilities - contingent consideration | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	0.0	0.0
Other noncurrent liabilities - contingent consideration | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	(4.7)	(69.0)
Other noncurrent liabilities - contingent consideration | Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	(4.7)	(69.0)
Other noncurrent liabilities - contingent consideration | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	$ (4.7)	$ (69.0)