Derivative Financial Instruments and Hedging Activities (Textual) (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 30, 2025	Apr. 30, 2024
Derivative Instruments and Hedging Activities [Line Items]
Maximum Remaining Maturity of Foreign Currency Derivatives	24 months	24 months
Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months	$ (8)
Derivative, Net Liability Position, Aggregate Fair Value	12	$ 1
Finlandia
Derivative Instruments and Hedging Activities [Line Items]
Net investment hedge gain (Note 16)	26
Foreign Exchange Contract [Member]
Derivative Instruments and Hedging Activities [Line Items]
Derivative, Notional Amount	463	566
Designated as Hedging Instrument [Member] \| Net Investment Hedging [Member]
Derivative Instruments and Hedging Activities [Line Items]
Debt Instrument, Face Amount	531	497
4.75% senior notes, due April 15, 2033 {Member}
Derivative Instruments and Hedging Activities [Line Items]
Debt Instrument, Face Amount	$ 650	$ 650

Face (par) amount of debt instrument at time of issuance.

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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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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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Nominal or face amount used to calculate payment on derivative.

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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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Maximum amount of time remaining before foreign currency exchange rate derivatives mature or expire, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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