Financial Instruments (Interest Rate Management Contracts and Cross Currency Interest Rate Swaps) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2024	Sep. 30, 2024
Interest Rate Swaps Contracts \| Designated as hedging instrument \| Fair Value Hedges
Derivative [Line Items]
US$ Notional	$ 800.0	$ 800.0
Average Pay %	Secured Overnight Financing Rate (SOFR) [Member]	Secured Overnight Financing Rate (SOFR) [Member]
Average Receive %	1.64%	1.64%
Years Average Maturity	2 years 8 months 12 days	3 years
Interest Rate Swaps Contracts \| Designated as hedging instrument \| Cash flow hedges
Derivative [Line Items]
US$ Notional	$ 2,372.2	$ 2,159.3
Average Pay %	2.72%	2.72%
Average Receive %	SOFR	SOFR
Years Average Maturity	21 years	21 years 2 months 12 days
Interest Rate Swaps Contracts \| Not designated as hedging instrument
Derivative [Line Items]
US$ Notional	$ 506.7	$ 461.4
Average Pay %	3.27%	3.27%
Average Receive %	SOFR	SOFR
Years Average Maturity	20 years 2 months 12 days	20 years 6 months
Cross currency interest rate swaps \| Designated as hedging instrument \| Net investment hedges
Derivative [Line Items]
US$ Notional	$ 0.0	$ 16.7
Average Pay %	0.00%	5.39%
Average Receive %	0.00%	3.64%
Years Average Maturity	0 years	2 months 12 days
Cross currency interest rate swaps \| Designated as hedging instrument \| Cash flow hedges
Derivative [Line Items]
US$ Notional	$ 381.3	$ 410.6
Average Pay %	4.97%	4.96%
Average Receive %	2.84%	2.80%
Years Average Maturity	1 year 9 months 18 days	1 year 10 months 24 days
Cross currency interest rate swaps \| Not designated as hedging instrument
Derivative [Line Items]
US$ Notional	$ 0.0	$ 34.7
Average Pay %	0.00%	5.39%
Average Receive %	0.00%	3.64%
Years Average Maturity	0 years	2 months 12 days

Average pay interest rate related to the group of interest rate derivatives

No definition available.

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- Definition

Average receive interest rate related to group of interest rate derivatives.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the interest rate derivative and the maturity of the reference rate used.

+ References

No definition available.

+ Details

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- Definition

Indicates type of variable interest rate on debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

+ Details

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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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

+ Details

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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

+ Details

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- Details

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- Details

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- Details

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