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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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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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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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Fair Value Measurements (Details) - USD ($) $ in Millions	Jan. 31, 2019	Apr. 30, 2018	Jan. 31, 2018	Apr. 30, 2017
Assets:
Cash and cash equivalents, Carrying Amount	$ 260	$ 239	$ 287	$ 182
Cash and cash equivalents, Fair Value	260	239
Liabilities:
Short-term borrowings, Carrying Amount	207	215
Short-term borrowings, Fair Value	207	215
Long-term debt, Carrying Amount	2,301	2,341
Fair Value, Inputs, Level 2 [Member]
Assets:
Currency derivatives, Fair Value	24	1
Liabilities:
Currency derivatives, Fair Value	3	39
Long-term debt, Fair Value	2,361	2,386
Foreign Exchange Contract [Member]
Assets:
Currency derivatives, Carrying Amount	24	1
Liabilities:
Currency derivatives, Carrying Amount	$ 3	$ 39