Note 4 - Fair Value Measurements (Tables)
 3 Months Ended
Nov. 30, 2012
Fair Value, Assets Measured on Recurring Basis [Table Text Block]
       
Fair Value Measurements Using
 
   
 
Fair Value
   
(Level 1)
   
(Level 2)
   
(Level 3)
 
Assets:
                       
Short-term and Restricted Short-term Investments
                       
Certificates of deposit
  $ 213,514     $ —     $ 213,514     $ —  
Stock and bond mutual funds (a)
    29,208       29,208       —       —  
U.S. government and agency securities
    600       —       600       —  
Corporate bonds
    32,151       —       32,151       —  
Total
  $ 275,473     $ 29,208     $ 246,265     $ —  
                                 
Liabilities:
                               
Interest rate swap contract
  $ 6,375     $ —     $ 6,375     $ —  
Derivatives Not Designated as Hedging Instruments:
 
Other Current Assets
                               
Foreign currency forward assets
  $ 401     $ —     $ 401     $ —  
Other Accrued Liabilities
                               
Foreign currency forward liabilities
  $ 1     $ —     $ 1     $ —  
       
Fair Value Measurements Using
 
   
 
 
Fair Value
   
(Level 1)
   
(Level 2)
   
(Level 3)
 
Assets:
                       
Short-term and Restricted Short-term Investments
                       
Certificates of deposit
  $ 253,493     $ —     $ 253,493     $ —  
Stock and bond mutual funds (a)
    30,171       30,171       —       —  
U.S. government and agency securities
    603       —       603       —  
Corporate bonds
    36,626       —       36,626       —  
Total
  $ 320,893     $ 30,171     $ 290,722     $ —  
                                 
Liabilities:
                               
Interest rate swap contract
  $ 13,370     $ —     $ 13,370     $ —  
Derivatives Not Designated as Hedging Instruments:
 
Other Current Assets
                               
Foreign currency forward assets
  $ 1,482     $ —     $ 1,482     $ —  
Other Accrued Liabilities
                               
Foreign currency forward liabilities
  $ 158     $ —     $ 158     $ —  
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Table Text Block]
     
November 30,
 
 
Location of Gain (Loss) Recognized in Income on Derivatives
 
2012
   
2011
 
Derivatives Designated as Hedging Instruments:
             
Interest rate swap contract
Other comprehensive income (loss)
  $ 4.3     $ 4.8  
Derivatives Not Designated as Hedging Instruments:
                 
Foreign currency forward contracts
Other foreign currency transactions gains (losses), net
  $ (0.4 )   $ (2.7 )