Fair Values by Asset Category of Defined Benefit Pension Plan (Parenthetical) (Detail)	12 Months Ended
	Jun. 30, 2012
Large Cap Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value by asset category	77.00%
Emerging Markets Equity Fund
Defined Benefit Plan Disclosure [Line Items]
Fair value by asset category	14.00%
International Equity Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value by asset category	9.00%
Short Term Fixed Income Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Fair value by asset category	31.00%
High Yield Fixed Income Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Fair value by asset category	32.00%
Intermediate Fixed Income Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Fair value by asset category	11.00%
International Emerging Markets
Defined Benefit Plan Disclosure [Line Items]
Fair value by asset category	9.00%
Reits And Mlps Funds Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Fair value by asset category	17.00%