Employee Stock Purchase and Stock Option Plans (Stock Purchase and Stock Option Plans Information on the 1999 Plans) (Details) - shares	12 Months Ended
Sep. 27, 2019	Sep. 28, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	30,950,000
Number of remaining shares reserved for issuance at September 27, 2019 (in shares)	6,146,619
Number of shares relating to outstanding stock options at September 27, 2019 (in shares)	926,606
Number of shares available for future awards (in shares)	5,220,013	5,631,371
1999 SIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	29,850,000
Number of remaining shares reserved for issuance at September 27, 2019 (in shares)	5,719,617
Number of shares relating to outstanding stock options at September 27, 2019 (in shares)	755,856
Number of shares available for future awards (in shares)	4,963,761	5,335,741
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
Award number of shares, non-fungible share basis (in shares)	1
1999 ODSP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	1,100,000
Number of remaining shares reserved for issuance at September 27, 2019 (in shares)	427,002
Number of shares relating to outstanding stock options at September 27, 2019 (in shares)	170,750
Number of shares available for future awards (in shares)	256,252	295,630
Award number of shares, non-fungible share basis (in shares)	1.92

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.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
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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.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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