Marketable Securities (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2021	Oct. 01, 2021
Debt Securities, Available-for-sale [Line Items]
Document Period End Date	Dec. 31, 2021
Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	$ 137.0	$ 137.2
Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Noncurrent	3.5	7.1
US Treasury and Government [Member] \| Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	7.8	7.6
US Treasury and Government [Member] \| Other Noncurrent Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Noncurrent	3.4	6.0
Corporate Debt Securities [Member] \| Other Current Assets [Member]
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Current	121.5	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	7.7	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

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is YYYY-MM-DD.

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- Definition

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 current.

+ 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 http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26626-111562

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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.

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