Taxes on Earnings - Schedule of Changes in Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions	12 Months Ended
Oct. 02, 2015	Sep. 26, 2014	Sep. 27, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits balance–beginning of fiscal year	$ 49.6	$ 37.0	$ 38.8
Additions based on tax positions related to a prior year	0.0	10.7	2.5
Reductions based on tax positions related to a prior year	(9.9)	(0.3)	(0.7)
Additions based on tax positions related to the current year	5.7	8.2	6.6
Settlements	0.0	(0.4)	(4.2)
Reductions resulting from the expiration of the applicable statute of limitations	(5.9)	(5.6)	(6.0)
Unrecognized tax benefits balance–end of fiscal year	$ 39.5	$ 49.6	$ 37.0

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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