Divestiture charges, net.

No definition available.

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- Definition

Represents charges incurred to close or restructure a facility in connection with an exit or disposal activity. Such costs include clean-up costs and lease obligations. Costs are recorded as the activities are incurred except for lease obligation charges, which are recorded upon termination of the lease obligation or at the cease use date.

+ References

No definition available.

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- Definition

Represents severance and related benefit charges for the termination of employees under an exit or disposal activity. Charges are recorded either as one-time termination benefits, which are recognized ratable over the required service period to receive such benefit, or under an ongoing benefit plan arrangement once the charge is probable and reasonably estimable.

+ References

No definition available.

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- Definition

Total restructuring charges under exit or disposal plan.

+ References

No definition available.

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- Definition

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with 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
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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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 420
-SubTopic 10
-Section S99
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-Section 45
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Restructuring and Divestiture Charges - Charges Taken Related to Restructuring Actions (Detail) - USD ($) $ in Millions	3 Months Ended							12 Months Ended
	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Sep. 24, 2016	Mar. 26, 2016	Dec. 26, 2015	Sep. 30, 2017	Sep. 24, 2016	Sep. 26, 2015
Restructuring Cost and Reserve [Line Items]
Fiscal restructuring and divestiture charges	$ 2.5	$ 6.0	$ 1.6	$ 3.2	$ 2.9	$ 3.8	$ 2.3	$ 13.3	$ 10.5	$ 28.5
Fiscal 2015 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions										16.3
Facility closure costs										2.6
Fiscal restructuring charges										18.9
Divestiture net charges										9.6
Fiscal restructuring and divestiture charges										28.5
Fiscal 2016 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions									10.5
Fiscal restructuring charges									10.5
Two Thousand Seventeen [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions								8.5
Facility closure costs								4.8
Other								0.0
Fiscal restructuring charges								13.3
Fiscal 2017 Actions [Member] \| Fiscal 2015 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions										0.0
Facility closure costs										0.0
Fiscal restructuring charges										0.0
Fiscal 2017 Actions [Member] \| Fiscal 2016 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions									0.0
Fiscal restructuring charges									0.0
Fiscal 2017 Actions [Member] \| Two Thousand Seventeen [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions								8.5
Facility closure costs								0.0
Other								0.0
Fiscal restructuring charges								8.5
Fiscal 2016 Actions [Domain] \| Fiscal 2015 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions										0.0
Facility closure costs										0.0
Fiscal restructuring charges										0.0
Fiscal 2016 Actions [Domain] \| Fiscal 2016 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions									10.5
Fiscal restructuring charges									10.5
Fiscal 2016 Actions [Domain] \| Two Thousand Seventeen [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions								0.0
Facility closure costs								4.8
Other								0.0
Fiscal restructuring charges								4.8
Fiscal 2015 Actions [Member] \| Fiscal 2015 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions										10.0
Facility closure costs										0.0
Fiscal restructuring charges										10.0
Fiscal 2015 Actions [Member] \| Fiscal 2016 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions									0.0
Fiscal restructuring charges									0.0
Fiscal 2015 Actions [Member] \| Two Thousand Seventeen [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions								0.0
Facility closure costs								0.0
Other								0.0
Fiscal restructuring charges								0.0
Fiscal 2014 Actions [Member] \| Fiscal 2015 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions										6.0
Facility closure costs										2.0
Fiscal restructuring charges										8.0
Fiscal 2014 Actions [Member] \| Fiscal 2016 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions									0.0
Fiscal restructuring charges									0.0
Fiscal 2014 Actions [Member] \| Two Thousand Seventeen [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions								0.0
Facility closure costs								0.0
Other								0.0
Fiscal restructuring charges								0.0
Other Operating Cost Reductions [Member] \| Fiscal 2015 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions										0.3
Facility closure costs										0.6
Fiscal restructuring charges										$ 0.9
Other Operating Cost Reductions [Member] \| Fiscal 2016 Charges [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions									0.0
Fiscal restructuring charges									$ 0.0
Other Operating Cost Reductions [Member] \| Two Thousand Seventeen [Member] \| Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Workforce reductions								0.0
Facility closure costs								0.0
Other								0.0
Fiscal restructuring charges								$ 0.0