Restructuring - Summary of Restructuring Activities (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 26, 2015	Sep. 27, 2014
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	$ 50.2
2015	64.0
Utilization cash	(40.6)
Utilization non-cash	(3.5)
Accrual as of end of period	70.1
Employee termination benefits
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	45.1
2015	55.6
Utilization cash	(35.9)
Utilization non-cash	0.0
Accrual as of end of period	64.8
Asset impairment charges
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2015	1.6	$ 0.1
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	5.1
2015	1.6
Utilization cash	(1.4)
Utilization non-cash	0.0
Accrual as of end of period	5.3
Other related costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0.0
2015	5.2
Utilization cash	(3.3)
Utilization non-cash	(1.9)
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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- Definition

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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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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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

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-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.

+ References

No definition available.

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Amount of consideration other than cash used to fully or partially settle an accrued restructuring cost.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

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-Number Topic 5

-Section P

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