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Derivative Financial Instruments and Hedging Derivative Financial Instruments and Hedging Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Derivative [Line Items]
Financing portion of cash paid for rate-lock interest rate swaps	$ 0.0	$ (43.5)	$ 0.0
Not Designated as Hedging Instrument | Interest rate swap
Derivative [Line Items]
Derivative, Notional amount of terminated contracts	400.0	200.0
Derivative, Cash Received for Termination	5.2	6.7
Derivative, Notional Amount	$ 300.0	700.0
Not Designated as Hedging Instrument | Interest rate swap, rate lock swaps
Derivative [Line Items]
Derivative, Notional amount of terminated contracts		849.3	700.0
Derivative, Cash Settlements paid, net		55.1	$ 17.0
Not Designated as Hedging Instrument | Interest rate swap, options
Derivative [Line Items]
Derivative, Notional amount of terminated contracts		332.6
Derivative, Cash Settlements paid, net		$ 2.1

X

- Definition

Derivative, Cash Received for Termination

+ References

No definition available.

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- Definition

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+ References

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- Definition

Derivative, Notional amount of terminated contracts

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

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- Definition

The cash outflow for derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 23
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

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