Marketable Securities (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2022	Oct. 01, 2021
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Noncurrent, Maximum Contractual Maturity	2 years
Debt Securities, Available-for-sale, Current	$ 20.3	$ 137.2
Debt Securities, Available-for-sale, Noncurrent	0.5	7.1
US Treasury and Government [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	13.1	7.6
Debt Securities, Available-for-sale, Noncurrent	0.5	6.0
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	0.2	117.0
Debt Securities, Available-for-sale, Noncurrent	0.0	0.0
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	7.0	12.6
Debt Securities, Available-for-sale, Noncurrent	$ 0.0	$ 1.1

Date of maturity of a debt security categorized as neither trading nor held to maturity, string text

No definition available.

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+ References

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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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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124260329&loc=d3e26626-111562

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+ References

No definition available.

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