Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

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Fixed interest rate related to the interest rate derivative.

+ References

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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
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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
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Derivative instruments - Schedule of Cross-Currency Swaps (Details) € in Millions, £ in Millions, $ in Millions	Sep. 30, 2024 USD ($)	Sep. 30, 2024 EUR (€)	Sep. 30, 2024 GBP (£)
2.00% 2026 euro Notes \| Notes
Derivative [Line Items]
Interest rate, stated percentage	2.00%	2.00%	2.00%
5.50% 2026 pound sterling Notes \| Notes
Derivative [Line Items]
Interest rate, stated percentage	5.50%	5.50%	5.50%
4.00% 2029 pound sterling Notes \| Notes
Derivative [Line Items]
Interest rate, stated percentage	4.00%	4.00%	4.00%
Cash flow hedge \| Cross-currency swap contracts \| 2.00% 2026 euro Notes
Derivative [Line Items]
Notional amounts	$ 833	€ 750
Cash flow hedge \| Cross-currency swap contracts \| 5.50% 2026 pound sterling Notes
Derivative [Line Items]
Notional amounts	747		£ 475
Cash flow hedge \| Cross-currency swap contracts \| 4.00% 2029 pound sterling Notes
Derivative [Line Items]
Notional amounts	$ 1,111		£ 700
Cash flow hedge \| Cross-currency swap contracts \| Euro Member Countries, Euro \| 2.00% 2026 euro Notes
Derivative [Line Items]
Interest rates	2.00%	2.00%	2.00%
Cash flow hedge \| Cross-currency swap contracts \| United Kingdom, Pounds \| 5.50% 2026 pound sterling Notes
Derivative [Line Items]
Interest rates	5.50%	5.50%	5.50%
Cash flow hedge \| Cross-currency swap contracts \| United Kingdom, Pounds \| 4.00% 2029 pound sterling Notes
Derivative [Line Items]
Interest rates	4.00%	4.00%	4.00%
Cash flow hedge \| Cross-currency swap contracts \| United States of America, Dollars \| 2.00% 2026 euro Notes
Derivative [Line Items]
Interest rates	3.90%	3.90%	3.90%
Cash flow hedge \| Cross-currency swap contracts \| United States of America, Dollars \| 5.50% 2026 pound sterling Notes
Derivative [Line Items]
Interest rates	6.00%	6.00%	6.00%
Cash flow hedge \| Cross-currency swap contracts \| United States of America, Dollars \| 4.00% 2029 pound sterling Notes
Derivative [Line Items]
Interest rates	4.60%	4.60%	4.60%