Basis of Presentation and Major Accounting Policies (Schedule of Changes in Carrying Amount of Allowance for Credit Losses) (Details) $ in Millions	3 Months Ended
Dec. 31, 2020 USD ($)
Allowance for Credit Losses
Beginning balance	$ 23.9
Adoption of new credit losses standard	0.5
Provision for credit losses	1.0
Write-offs charged against the allowance	(0.8)
Currency translation and other	1.6
Ending balance	$ 26.2

Accounts Receivable, Allowance for Credit Loss, Increase (Decrease) For Foreign Currency Translation And Other

No definition available.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable from change in methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919244-210447

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
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-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446

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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.

+ References

No definition available.

+ Details

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Amount of direct write-downs of accounts receivable charged against the allowance.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

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