Marketable Securities (Details) - USD ($) $ in Millions	9 Months Ended
Jul. 01, 2022	Oct. 01, 2021
Debt Securities, Available-for-sale [Line Items]
Document Period End Date	Jul. 01, 2022
Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	$ 16.2	$ 137.2
Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Noncurrent	3.0	7.1
US Treasury and Government [Member] \| Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	8.0	7.6
US Treasury and Government [Member] \| Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Noncurrent	2.9	6.0
Corporate Debt Securities [Member] \| Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	0.0	117.0
Corporate Debt Securities [Member] \| Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Noncurrent	0.0	0.0
US States and Political Subdivisions Debt Securities [Member] \| Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	8.2	12.6
US States and Political Subdivisions Debt Securities [Member] \| Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Noncurrent	$ 0.1	$ 1.1

For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Topic 320
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-Section 45
-Paragraph 2
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