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Summary of Significant Accounting Policies (Schedule of Product Warranty Liability) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Accounting Policies [Abstract]
Balance at end of year	$ 9.7	$ 14.4	$ 17.1	$ 20.0
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at beginning of year	7.2
Product Warranty Expense	3.5	2.6	3.9
Warranty payments	(8.2)	(5.3)	$ (6.8)
Balance at end of year	$ 6.7	$ 7.2

X

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date, whether due within or after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249

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-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249

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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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- Definition

The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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