Fair Value Measurements (Schedule Of Items Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2013	Feb. 28, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	$ 759,759	$ 461,260
Mutual fund investments	5,396	4,024
Derivative instruments	1,662	0
Total assets at fair value	766,817	465,284
Percent of total assets at fair value	100.00%	100.00%
Percent of total assets	7.00%	4.70%
Derivative instruments	0	517
Total liabilities at fair value	0	517
Percent of total liabilities	0.00%	0.00%
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	759,759	461,260
Mutual fund investments	5,396	4,024
Derivative instruments	0	0
Total assets at fair value	765,155	465,284
Percent of total assets at fair value	99.80%	100.00%
Percent of total assets	7.00%	4.70%
Derivative instruments	0	0
Total liabilities at fair value	0	0
Percent of total liabilities	0.00%	0.00%
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	0	0
Mutual fund investments	0	0
Derivative instruments	1,662	0
Total assets at fair value	1,662	0
Percent of total assets at fair value	0.20%	0.00%
Percent of total assets	0.00%	0.00%
Derivative instruments	0	517
Total liabilities at fair value	$ 0	$ 517
Percent of total liabilities	0.00%	0.00%

Item as percentage of total assets

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Item as percentage of total assets at fair value

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Item as percentage of total liabilities

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

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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.

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-Publisher FASB

-Name Accounting Standards Codification

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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.

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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 assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial and nonfinancial obligations.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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