Weighted Average Assumptions of Fair Value of Stock Option Grant Estimated on Date of Grant Using Black-Scholes Option Pricing Model (Detail)	12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2011
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Method Used [Line Items]
Risk-free interest rate	0.50%	0.60%	1.20%
Expected life of options (in years)	3 years 9 months 18 days	3 years 8 months 16 days	3 years 8 months 12 days
Expected volatility	0.55%	0.55%	0.50%
Dividend yield	0.00%	0.00%	0.00%