Summary of Significant Accounting Policies - Schedule of Other Assets (Detail) - USD ($) $ in Millions	Sep. 24, 2016	Sep. 26, 2015
Accounting Policies [Abstract]
Cash Surrender Value of Life Insurance	$ 36.0	$ 27.5
Manufacturing access fees	9.6	11.6
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0.4	6.2
Mutual funds	0.0	5.6
Cost-method equity investments	3.5	4.2
Deferred Tax Assets, Gross, Noncurrent	9.3	0.0
Other	23.9	17.9
Other assets	$ 83.7	$ 88.2

The aggregate carrying value of the Company's cost-method investments at the balance sheet date.

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- Definition

Represents the net carrying value of a long-term prepaid manufacturing supply agreement.

+ References

No definition available.

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- Definition

Mutual Funds

+ References

No definition available.

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- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
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- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 4
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- Definition

The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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