Employee Benefit and Retirement Plans (Schedule Of Assumptions Used To Determine Benenfit Obligations And Earnings Effects For Pension Plans) (Details)	12 Months Ended
	Apr. 30, 2021	Apr. 30, 2020	Apr. 30, 2019
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.80%	3.16%
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.16%	4.02%	4.18%
Expected return on plan assets	3.25%	5.00%	5.50%