Fair Value Measurements - Fair Value of Financial Instruments (Details) - USD ($) $ in Millions	Oct. 01, 2021	Dec. 31, 2020
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible senior notes due 2025	$ 426.7	$ 411.1
Long-term debt	887.8	907.7
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible senior notes due 2025	1,097.2	902.7
Long-term debt	887.8	907.7
Interest rate swap derivative contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	3.5	8.3
Interest rate swap derivative contracts | Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	3.5	8.3
Interest rate swap derivative contracts | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	3.5	8.3
Cross-currency swap derivative contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	28.7	61.8
Cross-currency swap derivative contracts | Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	28.7	61.8
Cross-currency swap derivative contracts | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	$ 28.7	$ 61.8