Investments - Gross Unrealized Losses and Fair Values of Available-For-Sale Investment Securities with Unrealized Losses (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Jun. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	$ 5,082	$ 4,962
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	(92)	(245)
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Fair Value	34
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses	(8)
Available-for-Sale securities, Continuous Unrealized Loss Position, Fair Value	5,116	4,962
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(100)	(245)
Common stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value		135
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses		(52)
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Fair Value	34
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses	(8)
Available-for-Sale securities, Continuous Unrealized Loss Position, Fair Value	34	135
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(8)	(52)
Venture capital investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	163
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	(5)
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses
Available-for-Sale securities, Continuous Unrealized Loss Position, Fair Value	163
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(5)
Offshore fund [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	4,914	4,811
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	(86)	(189)
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses
Available-for-Sale securities, Continuous Unrealized Loss Position, Fair Value	4,914	4,811
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	(86)	(189)
Mutual funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	5	16
Available-for-sale securities, Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	(1)	(4)
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Fair Value
Available-for-sale securities, Continuous Unrealized Loss Position, 12 Months or Greater, Gross Unrealized Losses
Available-for-Sale securities, Continuous Unrealized Loss Position, Fair Value	5	16
Available-for-sale securities, Continuous Unrealized Loss Position, Gross Unrealized Losses, Total	$ (1)	$ (4)