Debt - Schedule of long-term debt (Details) - USD ($) $ in Millions	Mar. 30, 2019	Dec. 29, 2018
Debt Instrument [Line Items]
Total principal of debt	$ 3,000.3	$ 3,027.1
Deferred issuance costs	(46.5)	(48.7)
Accrued interest	9.3	26.6
Total carrying value of debt	2,963.1	3,005.0
Debt, current portion	34.2	51.6
Debt, less current portion	2,928.9	2,953.4
Secured debt: \| —Dollar Term Loan
Debt Instrument [Line Items]
Total principal of debt	1,707.7	1,716.4
Secured debt: \| —Euro Term Loan
Debt Instrument [Line Items]
Total principal of debt	724.4	742.1
Unsecured debt: \| —Dollar Senior Notes
Debt Instrument [Line Items]
Total principal of debt	568.0	568.0
Unsecured debt: \| —Other loans
Debt Instrument [Line Items]
Total principal of debt	$ 0.2	$ 0.6

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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-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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 of interest payable on debt, including, but not limited to, trade payables.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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