Contractual interest rate for funds borrowed, under the debt agreement.

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Financial Instruments - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Financial Instruments - Narrative (Details) - USD ($)	Oct. 02, 2020	Sep. 27, 2019	Oct. 02, 2020	Sep. 27, 2019	Apr. 17, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Foreign currency transaction gain (loss) realized	$ 100,000	$ 300,000	$ (3,400,000)	$ (3,800,000)
Convertible Debt \| 1.00% Notes
Derivatives, Fair Value [Line Items]
Debt instrument, interest rate (as a percent)	1.00%		1.00%
Convertible Debt \| 1.625% Notes
Derivatives, Fair Value [Line Items]
Debt instrument, interest rate (as a percent)	1.625%		1.625%
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Notional Amount	$ 213,700,000		$ 213,700,000			$ 183,300,000
Foreign currency exchange contracts \| Minimum
Derivatives, Fair Value [Line Items]
Derivative, term of contract (in months)			1 month
Foreign currency exchange contracts \| Maximum
Derivatives, Fair Value [Line Items]
Derivative, term of contract (in months)			3 months
Interest Rate Swap 1
Derivatives, Fair Value [Line Items]
Notional Amount					$ 1,250,000,000
Interest Rate Swap 2
Derivatives, Fair Value [Line Items]
Notional Amount					750,000,000.0
Interest Rate Swap 3
Derivatives, Fair Value [Line Items]
Notional Amount					$ 750,000,000.0
Interest Rate Swap
Derivatives, Fair Value [Line Items]
Notional Amount	$ 2,250,000,000	$ 1,000,000,000.0	$ 2,250,000,000	$ 1,000,000,000.0