Retirement Benefit Obligations - Schedule of Weighted-Average Asset Allocations, by Asset Category (Detail)	Jun. 30, 2014	Jun. 30, 2013
Asset Category:
Benefit plan weighted-average asset allocations	100.00%	100.00%
Equity Securities [Member]
Asset Category:
Benefit plan weighted-average asset allocations	30.00%	37.00%
Debt Securities [Member]
Asset Category:
Benefit plan weighted-average asset allocations	52.00%	39.00%
Cash and Other [Member]
Asset Category:
Benefit plan weighted-average asset allocations	18.00%	24.00%