Fair Value - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Jun. 30, 2013
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total available-for-sale securities	$ 380,977	$ 350,521
Level 1 [Member] \| Money Market [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total available-for-sale securities	380,977	350,521
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total available-for-sale securities	18,566	16,969
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	18,566	16,969
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 recorded for business combination	$ 102,444	$ 8,247