Restructuring - Summary of Restructuring Activities (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2018	Jul. 01, 2017
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	$ 98.0
2018 charges	28.4
Utilization cash	(27.0)
Utilization, non-cash	(1.6)
Accrual as of end of period	97.8
Employee termination benefits
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	93.0
2018 charges	23.3
Utilization cash	(23.7)
Utilization, non-cash	0.0
Accrual as of end of period	92.6
Asset impairment charges
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2018 charges	1.6	$ 0.4
Utilization cash	0.0
Utilization, non-cash	(1.6)
Accrual as of end of period	0.0
Contract termination costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	5.0
2018 charges	0.5
Utilization cash	(0.3)
Utilization, non-cash	0.0
Accrual as of end of period	5.2
Other related costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2018 charges	3.0
Utilization cash	(3.0)
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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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