Employee Benefit And Retirement Plans (Schedule Of Allocation Of Plan Assets)(Details)	12 Months Ended
	Apr. 30, 2013	Apr. 30, 2012
Defined Benefit Plan Disclosure [Line Items]
Plan asset actual allocation	100.00%	100.00%
Plan asset target allocation	100.00%
Equity Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset actual allocation	50.20%	49.50%
Plan asset target allocation	50.00%
Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan asset actual allocation	49.80%	50.50%
Plan asset target allocation	50.00%