v2.4.0.6
Fair Value Measurements (Schedule Of Items Measured At Fair Value On A Recurring Basis) (Details) (USD $)
Nov. 30, 2011
Feb. 28, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market securities $ 400,800,000 $ 50,600,000
Mutual fund investments 2,200,000  
Derivative instruments 1,100,000 3,200,000
Total assets at fair value 404,100,000 53,800,000
Percent of total assets at fair value 100.00% 100.00%
Percent of total assets 5.30% 0.80%
Derivative instruments 1,200,000 3,800,000
Total liabilities at fair value 1,200,000 3,800,000
Percent of total liabilities 0.00% 0.10%
Retained interest 0 0
Level 1 [Member]
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market securities 400,800,000 50,600,000
Mutual fund investments 2,200,000  
Derivative instruments 0 0
Total assets at fair value 403,000,000 50,600,000
Percent of total assets at fair value 99.70% 94.00%
Percent of total assets 5.30% 0.70%
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  
Derivative instruments 1,100,000 3,200,000
Total assets at fair value 1,100,000 3,200,000
Percent of total assets at fair value 0.30% 6.00%
Percent of total assets 0.00% 0.00%
Derivative instruments 1,200,000 3,800,000
Total liabilities at fair value $ 1,200,000 $ 3,800,000
Percent of total liabilities 0.00% 0.10%