v2.4.0.6

Fair Value Measurements (Schedule Of Items Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	Feb. 29, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	$ 427,952	$ 458,090
Mutual fund investments	3,793	2,586
Derivative instruments	0	317
Total assets at fair value	431,745	460,993
Percent of total assets at fair value	100.00%	100.00%
Percent of total assets	4.60%	5.50%
Derivative instruments	1,512	1,978
Total liabilities at fair value	1,512	1,978
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	427,952	458,090
Mutual fund investments	3,793	2,586
Derivative instruments	0	0
Total assets at fair value	431,745	460,676
Percent of total assets at fair value	100.00%	99.90%
Percent of total assets	4.60%	5.50%
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	0	317
Total assets at fair value	0	317
Percent of total assets at fair value	0.00%	0.10%
Percent of total assets	0.00%	0.00%
Derivative instruments	1,512	1,978
Total liabilities at fair value	$ 1,512	$ 1,978
Percent of total liabilities	0.00%	0.00%

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