Debt and Credit Facilities (Components Of Debt) (Details)	Oct. 02, 2020 USD ($)	Oct. 02, 2020 EUR (€)	May 21, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 20, 2019 USD ($)	Sep. 20, 2019 EUR (€)
Debt Instrument [Line Items]
Total debt	$ 1,759,300,000			$ 1,324,900,000
Less: current portion	(3,800,000)			(3,900,000)
Long-term debt	1,755,500,000			1,321,000,000.0
Senior term loan facility due 2022 ($650.0 million aggregate principal amount) (the “Term Loan Facility”), net of deferred debt issuance costs of $2.1 million and $1.3 million, respectively
Debt Instrument [Line Items]
Debt issuance costs	2,100,000			1,300,000
Total debt	647,900,000			648,700,000	$ 650,000,000.0
Term loan					$ 650,000,000.0
Senior euro term loan facility due 2022 (€600.0 million aggregate principal amount) (the “Euro Term Loan Facility”), net of deferred debt issuance costs of $1.5 million and $0.9 million, respectively
Debt Instrument [Line Items]
Debt issuance costs	1,500,000			900,000
Total debt	701,500,000			672,000,000.0
Term loan | €		€ 600,000,000.0				€ 600,000,000.0
Other
Debt Instrument [Line Items]
Total debt	3,800,000			4,200,000
Convertible Debt | Convertible senior notes, net of deferred debt issuance costs of $11.3 million and unamortized discount of $100.1 million
Debt Instrument [Line Items]
Debt issuance costs	11,300,000		$ 11,900,000
Unamortized discount	100,100,000
Interest rate			2.375%
Total debt	$ 406,100,000		$ 410,900,000	$ 0
Term loan			$ 517,500,000