Shareholders' Equity - Restricted Stock Units (Detail) - $ / shares shares in Millions	3 Months Ended
Jan. 01, 2016	Oct. 02, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Numbers of Shares, Beginning Balance	2.6	3.0
Restricted stock, Number of Shares Granted	0.1	1.2
Restricted Stock, Number of Shares Vested	(0.1)	(1.5)
Restricted stock, Number of Shares Forfeited	(0.1)	(0.1)
Numbers of Shares, Ending Balance	2.5	2.6
Number of share, Expected to vest after January 1, 2016	2.4
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Grant Date Fair Value Per Share, Beginning Balance	$ 84.43	$ 73.80
Restricted stock, Granted, Weighted Average Grant Date Fair Value Per Share	68.31	84.39
Restricted Stock, Vested, Weighted Average Grant Date Fair Value Per Share	61.61	62.14
Restricted stock, Forfeited, Weighted Average Grant Date Fair Value Per Share	85.31	81.55
Weighted Average Grant Date Fair Value Per Share, Ending Balance	84.71	$ 84.43
Weighted Average Grant Date Fair Value Per Share, Expected to vest after January 1, 2016	$ 84.57

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options assumed in period in a business combination.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options assumed in period in a business combination weighted average grant date fair value.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options expected to vest outstanding number.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options expected to vest outstanding weighted average grant date fair value.

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