Convertible Units, Conversion Date

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- Definition

Investment Interest Rate, Percentage

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No definition available.

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- Definition

Percentage of Carrying Value over Fair Value

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No definition available.

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- Definition

The gross realized gain on investments sold during the period.

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No definition available.

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- Definition

The gross realized loss on investments sold during the period.

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- Definition

Investments in debt and equity securities which are categorized neither as trading securities nor held-to-maturity securities and which are intended be sold or mature within one year from the balance sheet date or the normal operating cycle, whichever is longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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- Definition

Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

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- Definition

Value of the investment at close of period. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Marketable Securities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended			1 Months Ended
	May 31, 2012	May 31, 2011	May 31, 2012 Maximum	Apr. 30, 2012 Investment in Kemrock convertible debt	Apr. 30, 2012 Investment in Kemrock convertible debt Maximum	Apr. 30, 2012 Investment in Kemrock convertible debt Minimum
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, current	$ 106.5	$ 113.8
Available-for-sale securities, long-term	22.7	35.8
Investment in affiliate				22.7
Investment in affiliate, interest rate				5.50%
Debt securities, conversion date					Jun. 12, 2017	Jun. 04, 2012
Gross gains realized on sales of investments	4.1	13.3
Gross losses realized on sales of investments	5.0	3.6
Losses recognized for securities deemed to have other-than-temporary impairments	$ 1.6	$ 0.7
Investments with unrealized loss, percentage of fair values less than original cost			15.00%