Employee Stock Purchase and Stock Option Plans (Stock Purchase and Stock Option Plans Information on the 1999 Plans) (Details) - shares	12 Months Ended
Sep. 29, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	30,950,000
Number of remaining shares reserved for issuance at September 29, 2017	10,181,183
Number of shares relating to outstanding stock options at September 29, 2017	2,516,825
Number of shares available for future awards (in shares)	7,664,358	7,552,708
1999 SIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	29,850,000
Number of remaining shares reserved for issuance at September 29, 2017	9,641,396
Number of shares relating to outstanding stock options at September 29, 2017	2,289,450
Number of shares available for future awards (in shares)	7,351,946	7,233,173
1999 SIP \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award number of shares, non-fungible share basis (in shares)	1
1999 SIP \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award number of shares, non-fungible share basis (in shares)	1
1999 SIP \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award number of shares, fungible share basis (in shares)	1.92
Award number of shares, non-fungible share basis (in shares)	1
1999 SIP \| Other than Option Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award number of shares, fungible share basis (in shares)	1.92
1999 ODSP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,100,000
Number of remaining shares reserved for issuance at September 29, 2017	539,787
Number of shares relating to outstanding stock options at September 29, 2017	227,375
Number of shares available for future awards (in shares)	312,412	319,535
Award number of shares, non-fungible share basis (in shares)	1

Share-based compensation arrangement by share-based payment award, award number of shares, fungible share basis.

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- Definition

Share-based compensation arrangement by share-based payment award, award number of shares, non-fungible share basis.

+ References

No definition available.

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ 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 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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