Marketable Securities (Details) - USD ($) $ in Thousands	Jul. 02, 2021	Oct. 02, 2020
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	$ 0
Available-for-sale Securities, Gross Unrealized Loss	0
Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	129,200	$ 408,100
Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	3,900	5,200
US Treasury and Government [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		300
US Treasury and Government [Member] \| Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	10,500	129,400
US Treasury and Government [Member] \| Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	3,300	5,000
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		200
Corporate Debt Securities [Member] \| Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	106,800	276,800
Corporate Debt Securities [Member] \| Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	0	0
US States and Political Subdivisions Debt Securities [Member] \| Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	11,900	1,900
US States and Political Subdivisions Debt Securities [Member] \| Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities	$ 600	$ 200

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

+ Details

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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