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Percentage Of Foreign Exchange Rate Exposure Hedged Minimum

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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Nominal or face amount used to calculate payments on the derivative asset.

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Average fixed interest rate related to the group of interest rate derivatives.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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Amount of gain (loss) from excluded component of derivative hedge, recognized in earnings. Excludes recognition under systematic and rational method.

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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.

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Nominal or face amount used to calculate payment on derivative.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Amount, before tax and reclassification, of gain (loss) from derivative designated and qualifying as net investment hedge.

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Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from derivative designated and qualifying as net investment hedge.

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Derivative Instruments and Hedging Activities - Narrative (Details) € in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2025 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Oct. 31, 2025 USD ($)	Oct. 31, 2025 CNY (¥)	Sep. 30, 2025 EUR (€)	Jun. 30, 2025 USD ($)	Jun. 30, 2025 CNY (¥)	Sep. 30, 2024 CNY (¥)	Aug. 30, 2024	Jun. 30, 2024 USD ($)	Jun. 30, 2024 CNY (¥)	Mar. 31, 2024 USD ($)	Mar. 31, 2024 CNY (¥)	Mar. 31, 2023 USD ($)	Mar. 31, 2023 CNY (¥)
Derivative [Line Items]
Percentage of foreign exchange rate exposure hedged, minimum (as percent)	70.00%	70.00%					70.00%
Percentage of foreign exchange rate exposure hedged, maximum (as percent)	90.00%	90.00%					90.00%
Cash collateral pledged	$ 0	$ 0	$ 0
Cash collateral received	0	0	0
Pretax gain on cash flow hedges	28,000,000	28,000,000
7.50% Notes due in 2033 \| Unsecured debt
Derivative [Line Items]
Long-term debt, gross \| €							€ 123
7.50% Notes due in 2033 \| Unsecured debt \| Derivatives and Hedging Activities Designated as Hedging Instruments under ASC 815
Derivative [Line Items]
Interest rate (as percent)											3.50%
Cash flow hedging
Derivative [Line Items]
Derivative, excluded component, gain (loss), recognized in earnings		0	0	$ 0
Interest Rate Swap \| Net investment hedging
Derivative [Line Items]
Derivative, notional amount	$ 325,000,000	$ 325,000,000
Derivative, term of contract	3 years
Interest Rate Swap \| Net investment hedging \| Long
Derivative [Line Items]
Derivative, average fixed interest rate (as percent)	1.85%	1.85%					1.85%
Interest Rate Swap \| Net investment hedging \| Short
Derivative [Line Items]
Derivative, average fixed interest rate (as percent)	0.00%	0.00%					0.00%
Cross-currency interest rate swaps \| Net investment hedging \| China
Derivative [Line Items]
Notional value of derivative asset			17,000,000					$ 78,000,000	¥ 559,000,000	¥ 120,000,000		$ 78,000,000	¥ 570,000,000	$ 96,000,000	¥ 685,000,000	$ 35,000,000	¥ 240,000,000
Cross-currency interest rate swaps \| Net investment hedging \| China \| Subsequent Event
Derivative [Line Items]
Notional value of derivative asset					$ 56,000,000	¥ 413,000,000
Foreign currency exchange derivatives \| Net investment hedging
Derivative [Line Items]
Effective portion of pretax gains (loss) related to net investment hedges		$ (5,000,000)	(5,000,000)	(67,000,000)
Gains (losses) reclassified into income for net investment hedges		$ 0	$ 0	$ 0