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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

+ References

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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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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.

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Long-Term Assets - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 75.0	$ 71.3	$ 217.9	$ 207.2
Restructuring charges			64.0
Fixed asset impairment charges			0.5
Asset impairment charges
Property, Plant and Equipment [Line Items]
Restructuring charges			$ 1.6	$ 0.1