Restructuring - Summary of Restructuring Activities (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 28, 2015
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	$ 50.2us-gaap_RestructuringReserve
Restructuring charges	7.3us-gaap_RestructuringCharges
Utilization cash	(11.0)us-gaap_PaymentsForRestructuring
Utilization non-cash	(1.1)
Accrual as of end of period	45.4us-gaap_RestructuringReserve
Employee termination benefits
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	45.1
Restructuring charges	4.5
Utilization cash	(9.5)
Utilization non-cash	0
Accrual as of end of period	40.1
Asset impairment charges
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0
Restructuring charges	1.1
Utilization cash	0
Utilization non-cash	(1.1)
Accrual as of end of period	0
Contract termination costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	5.1
Restructuring charges	1.0
Utilization cash	(0.8)
Utilization non-cash	0
Accrual as of end of period	5.3
Other related costs
Restructuring Reserve [Roll Forward]
Accrual as of beginning of period	0
Restructuring charges	0.7
Utilization cash	(0.7)
Utilization non-cash	0
Accrual as of end of period	$ 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

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 3: 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))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.P.3)

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

+ Details

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- Definition

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))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

+ Details

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- Definition

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

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

Reference 3: 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)(2))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

+ Details

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