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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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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 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 of Financial Instruments (Details) - USD ($) $ in Millions	Jul. 31, 2016	Apr. 30, 2016	Jul. 31, 2015	Apr. 30, 2015
Assets:
Cash and cash equivalents, Carrying Amount	$ 459	$ 263	$ 494	$ 370
Cash and cash equivalents, Fair Value	459	263
Liabilities:
Short-term borrowings, Carrying Amount	288	271
Short-term borrowings, Fair Value	288	271
Long-term debt, Carrying Amount	1,953	1,230
Long-term debt, Fair Value	2,122	1,293
Currency derivatives [Member]
Assets:
Currency derivatives, Fair Value	28	19
Liabilities:
Currency derivatives, Fair Value	5	10
Reported Value Measurement [Member]
Assets:
Cash and cash equivalents, Carrying Amount	459	263
Liabilities:
Short-term borrowings, Carrying Amount	288	271
Long-term debt, Carrying Amount	1,953	1,230
Reported Value Measurement [Member] \| Currency derivatives [Member]
Assets:
Currency derivatives, Carrying Amount	28	19
Liabilities:
Currency derivatives, Carrying Amount	$ 5	$ 10