Long-Term Debt Narrative (Details) - USD ($) $ in Millions	Mar. 29, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt issuance costs	$ 31.4	$ 33.5
Long-term debt	2,931.1
Debt, principal balance outstanding	$ 2,931.1	2,939.0
1.00% Notes
Debt Instrument [Line Items]
Debt instrument, interest rate (as a percent)	1.00%
1.00% Notes \| Convertible Debt
Debt Instrument [Line Items]
Debt issuance costs	$ 5.1	5.8
Debt instrument, interest rate (as a percent)	1.00%
Debt, principal balance outstanding	$ 690.0	$ 690.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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