Restructuring - Summary of Restructuring Activities (Detail) - USD ($) $ in Millions	9 Months Ended
Oct. 01, 2016	Sep. 26, 2015
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	$ 71.8
2016 Charges	51.2
Utilization cash	(48.1)
Utilization, Non-cash	(3.5)
Accrual as of end of period	71.4
Employee termination benefits
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	66.5
2016 Charges	45.4
Utilization cash	(45.1)
Utilization, Non-cash	0.0
Accrual as of end of period	66.8
Asset impairment charges
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2016 Charges	3.5	$ 1.6
Utilization cash	0.0
Utilization, Non-cash	(3.5)
Accrual as of end of period	0.0
Contract termination costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	5.3
2016 Charges	(0.3)
Utilization cash	(0.4)
Utilization, Non-cash	0.0
Accrual as of end of period	4.6
Other related costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2016 Charges	2.6
Utilization cash	(2.6)
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.

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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-Section 45
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-URI http://asc.fasb.org/extlink&oid=66902209&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
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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
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-Topic 420
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-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
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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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