Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
Apr. 02, 2020	Mar. 28, 2019
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (163.0)	$ 163.1
Foreign currency translation adjustments	(35.8)	9.4
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	(93.2)	(0.3)
Unrealized foreign exchange (loss) gain on intercompany loan, net of tax effect of $0.9 and ($0.2) for the three months ended, respectively	(2.9)	0.9
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax	(9.8)
Unrealized Gain (Loss) on Interest Rate Cash Flow Hedges, Pretax, Accumulated Other Comprehensive Income (Loss)	(12.9)	0.0
Total other comprehensive (loss) gain	(141.7)	10.0
Total comprehensive (loss) income	$ (304.7)	$ 173.1

Other Comprehensive Income Unrealized Gain Loss On Intercompany Loan Net Of Tax

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of unrealized gain (loss) related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

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