Restructuring - Summary of Restructuring Activities (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2017	Oct. 01, 2016
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	$ 74.0
2017 charges	47.8
Utilization cash	(33.8)
Utilization, Non-cash	(0.4)
Accrual as of end of period	87.6
Employee termination benefits
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	69.4
2017 charges	41.0
Utilization cash	(27.7)
Utilization, Non-cash	0.0
Accrual as of end of period	82.7
Asset impairment charges
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2017 charges	0.4	$ 3.5
Utilization cash	0.0
Utilization, Non-cash	(0.4)
Accrual as of end of period	0.0
Contract termination costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	4.6
2017 charges	1.5
Utilization cash	(1.2)
Utilization, Non-cash	0.0
Accrual as of end of period	4.9
Other related costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2017 charges	4.9
Utilization cash	(4.9)
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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 5.P.3)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 420
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