Fair Value of Financial Instruments (Details) (USD $) In Millions, unless otherwise specified	Apr. 30, 2015	Apr. 30, 2014
Assets:
Cash and cash equivalents	$ 370	$ 437
Derivative assets	59us-gaap_DerivativeAssets	7us-gaap_DerivativeAssets
Liabilities:
Derivative liabilities	18us-gaap_DerivativeLiabilities	7us-gaap_DerivativeLiabilities
Short-term borrowings	190us-gaap_ShortTermBorrowings	8us-gaap_ShortTermBorrowings
Short-term borrowings	190us-gaap_ShorttermDebtFairValue	8us-gaap_ShorttermDebtFairValue
Current portion of long-term debt	250us-gaap_LongTermDebtCurrent	0us-gaap_LongTermDebtCurrent
Current portion of long-term debt	253	0
Long-term Debt, Excluding Current Maturities	748us-gaap_LongTermDebtNoncurrent	997us-gaap_LongTermDebtNoncurrent
Long-term debt	735us-gaap_LongTermDebtFairValue	963us-gaap_LongTermDebtFairValue
Foreign Exchange Contract [Member]
Assets:
Currency derivatives, assets	59	7
Liabilities:
Currency derivatives, liabilities	18	7
Reported Value Measurement [Member]
Assets:
Cash and cash equivalents	370	437
Liabilities:
Short-term borrowings	190	8
Current portion of long-term debt	250	0
Long-term Debt, Excluding Current Maturities	748	997
Reported Value Measurement [Member] \| Foreign Exchange Contract [Member]
Assets:
Currency derivatives, assets	59	7
Liabilities:
Currency derivatives, liabilities	$ 18	$ 7

Current portion of long term debt fair value disclosure.

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value, after the effects of master netting arrangements, of a 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. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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-Topic 210

-SubTopic 20

-Section 55

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226008-175313

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled 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.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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-Publisher FASB

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- Definition

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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-Name Regulation S-X (SX)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph 2, 3

-Article 9

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity 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. This item represents the amount of short-term debt existing as of the balance sheet date.

+ References

No definition available.

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