Summary of Significant Accounting Policies - Schedule of Other Assets (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Sep. 24, 2016
Accounting Policies [Abstract]
Life insurance contracts	$ 41.0	$ 36.0
Capitalized software	12.3	10.0
Manufacturing access fees	7.1	9.6
Cost-method equity investments	3.0	3.5
Deferred tax assets	9.1	9.3
Other	24.5	15.3
Other assets	$ 97.0	$ 83.7

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

No definition available.

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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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- References

No definition available.

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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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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 allowance, of deferred tax asset attributable to deductible temporary differences and carryforwards, classified as noncurrent.

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

Amount of assets classified as other.

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Amount of noncurrent assets classified as other.

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