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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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 includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

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

Fair value as of the balance sheet date of the gross assets less the gross liabilities of a derivative asset or group of derivative assets.

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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.

+ References

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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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- Definition

Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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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.

+ References

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Fair Value of Financial Instruments (Details) (USD $) In Millions	Jul. 31, 2011	Apr. 30, 2011	Jul. 31, 2010	Apr. 30, 2010
Assets:
Cash and cash equivalents, Carrying Amount	$ 552.5	$ 567.1	$ 260.8	$ 231.6
Cash and cash equivalents, Fair Value	552.5
Liabilities:
Short-term borrowings, Carrying Amount	1.9	0
Short-term borrowings, Fair Value	1.9
Current portion of long-term debt, Carrying Amount	254.4	254.9
Current portion of long-term debt, Fair Value	262.3
Long-term debt, Carrying Amount	505.1	504.5
Long -term debt, Fair Value	535.7
Commodity derivatives [Member]
Assets:
Contracts, Carrying Amount	2.6
Contracts, fair value	2.6
Currency Derivatives [Member]
Liabilities:
Currency derivatives, Carrying Amount	18.9
Currency derivatives, Fair Value	18.9
Interest Rate Swap [Member]
Assets:
Contracts, Carrying Amount	4.7
Contracts, fair value	$ 4.7