v2.4.0.6
Fair Value Of Financial Instruments (Summary Of Financial Assets And Liabilities Measured At Fair Value On Recurring Basis) (Detail) (USD $)
In Millions, unless otherwise specified
Jun. 30, 2012
Jun. 30, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market funds $ 160.9 $ 150.4
Available-for-sale equity securities   2.0
Available-for-sale equity securities 7.0 14.0
Total 167.9 166.4
Fair Value, Inputs, Level 1 [Member]
   
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market funds 160.9 150.4
Available-for-sale equity securities   2.0
Available-for-sale equity securities 7.0 14.0
Total 167.9 166.4
Fair Value, Inputs, Level 2 [Member]
   
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market funds      
Available-for-sale equity securities     
Available-for-sale equity securities      
Total      
Fair Value, Inputs, Level 3 [Member]
   
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Money market funds      
Available-for-sale equity securities     
Available-for-sale equity securities      
Total