v2.4.0.8
Fair Value - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)
Sep. 30, 2013
Jun. 30, 2013
Auction Rate Securities [Member]
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities $ 17,536,000 $ 16,969,000
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 326,066,000 350,521,000
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Money Market [Member]
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 326,066,000 350,521,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 17,536,000 16,969,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Auction Rate Securities [Member]
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 17,536,000 16,969,000
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Contingent Consideration Liability Recorded for Business Combination [Member]
    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Contingent consideration liability business combination fair value $ 8,505,000 $ 8,247,000