Restructuring - Summary of Restructuring Activities (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	$ 108.7
2019 charges	54.3
Utilization cash	(27.9)
Utilization, non-cash	(2.1)
Accrual as of end of period	133.0
Employee termination benefits
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	103.3
2019 charges	49.1
Utilization cash	(25.5)
Utilization, non-cash	0.0
Accrual as of end of period	126.9
Asset impairment charges
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2019 charges	2.1	$ 0.9
Utilization cash	0.0
Utilization, non-cash	(2.1)
Accrual as of end of period	0.0
Contract termination costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	5.4
2019 charges	1.5
Utilization cash	(0.8)
Utilization, non-cash	0.0
Accrual as of end of period	6.1
Other related costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2019 charges	1.6
Utilization cash	(1.6)
Utilization, non-cash	0.0
Accrual as of end of period	$ 0.0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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