Revenue Recognition - Schedule of Changes in Warranty Liability and Unearned Extended Warranty Premiums (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2021	Dec. 31, 2022	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Abstract]
Balance at beginning of period	$ 65.8	$ 66.9	$ 64.4	$ 68.2
Deferred revenue for new service-type warranties	6.4	31.5	26.2	23.6
Amortization of deferred revenue	(5.3)	(21.7)	(25.0)	(27.9)
Foreign currency translation		(0.6)	0.2	0.5
Balance at end of period	$ 66.9	$ 76.1	$ 65.8	$ 64.4

Product warranty amortization.

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- References

No definition available.

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- Definition

Amount as of the balance sheet date of the aggregate extended product warranty liability. Does not include the ending balance for the standard product warranty liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1),(c)(5)
-URI https://asc.fasb.org/extlink&oid=126907703&loc=d3e12565-110249

+ Details

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) the extended product warranty accrual. Excludes standard product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126907703&loc=d3e12565-110249

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- Definition

Amount of increase in the extended product warranty accrual from warranties issued. Excludes standard product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(3)
-URI https://asc.fasb.org/extlink&oid=126907703&loc=d3e12565-110249

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