Schedule of Net Periodic Pension Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Defined Benefit Plan Net Periodic Benefit Cost [Abstract]
Service cost	$ 2,791	$ 3,375
Interest cost	744	812
Expected return on plan assets	(1,106)	(1,338)
Net period pension cost	$ 2,429	$ 2,849