Fair Value Measurements Fair Value Measurements (Details) - USD ($) $ in Millions	Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2020
Assets:
Cash and cash equivalents, Carrying Amount	$ 868	$ 1,150	$ 675
Cash and cash equivalents, Fair Value	868	1,150
Liabilities:
Short-term borrowings, Carrying Amount	0	205
Short-term borrowings, Fair Value	0	205
Long-term debt (including current portion), Carrying Amount	2,269	2,354
Fair Value, Inputs, Level 2 [Member]
Assets:
Currency derivatives, Fair Value	48	3
Liabilities:
Currency derivatives, Fair Value	1	31
Long-term debt (including current portion), Fair Value	2,239	2,663
Foreign Exchange Contract [Member]
Assets:
Currency derivatives, Carrying Amount	48	3
Liabilities:
Currency derivatives, Carrying Amount	$ 1	$ 31

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Carrying amount as of the balance sheet date of the asset arising from derivative instruments and hedging activities, which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer.

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Sum as of the balance sheet date of the (a) fair values of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and (b) the carrying amounts of the liabilities arising from financial instruments or contracts used to mitigate a specified risk (hedge), and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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