Fair Value Measurements (Schedule Of Items Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Feb. 28, 2014	Feb. 28, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	$ 641,622	$ 461,260
Mutual fund investments	5,609	4,024
Total assets at fair value	647,231	465,284
Percent of total assets at fair value	100.00%	100.00%
Percent of total assets	5.50%	4.70%
Derivative instruments	1,351	517
Total liabilities at fair value	1,351	517
Percent of total liabilities	0.00%	0.00%
Fair Value, Equity, Level 1 to Level 2 Transfers, Description	0	0
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Money market securities	641,622	461,260
Mutual fund investments	5,609	4,024
Total assets at fair value	647,231	465,284
Percent of total assets at fair value	100.00%	100.00%
Percent of total assets	5.50%	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
Total assets at fair value	0	0
Percent of total assets at fair value	0.00%	0.00%
Percent of total assets	0.00%	0.00%
Derivative instruments	1,351	517
Total liabilities at fair value	$ 1,351	$ 517
Percent of total liabilities	0.00%	0.00%