Revenue Recognition - Schedule of Changes in Warranty Liability and Unearned Extended Warranty Premiums (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Disaggregation Of Revenue [Abstract]
Balance at beginning of period	$ 68.2	$ 30.7
Adoption of ASC 606		35.7
Deferred revenue for new service-type warranties	23.6	27.5
Amortization of deferred revenue	(27.9)	(25.2)
Foreign currency translation	0.5	(0.5)
Balance at end of period	$ 64.4	$ 68.2

Extended product warranty accrual, increase for adoption of ASU 2014-09.

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- Definition

Product warranty amortization.

+ References

No definition available.

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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 http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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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 http://asc.fasb.org/extlink&oid=68068213&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 http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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