Stock-Based Compensation (Schedule Of Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Apr. 30, 2021	Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Oustanding number of options, Beginning Balance	0	5,167	17,968
Options exercised	0	(5,167)	(12,801)
Oustanding number of options ending balance	0	0	5,167	17,968
Remaining contractual term outstanding	0 years	0 years	6 years 1 month 6 days	4 years 6 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Exercise price, beginning	$ 0	$ 57.11	$ 44.23
Exercise price, exercised	0	57.11	39.04
Exercise price, ending	$ 0	$ 0	$ 57.11	$ 44.23
Aggregate intrinsic value outstanding, beginning balance	$ 0	$ 170	$ 682
Aggregate intrinsic value, exercised	0	0	651
Aggregate intrinsic value outstanding, ending balance	$ 0	$ 0	$ 170	$ 682
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Vested and expected to vest in the future, Number of options	0
Vested and expected to vest in the future, Remaining contractual term	0 years
Vested and expected to vest in the future, Exercise price	$ 0
Vested and expected to vest in the future, Aggregate intrinsic value	$ 0
Exercisable, Number of options	0
Exercisable, Remaining contractual term	0 years
Exercisable, Exercise price	$ 0
Exercisable, Aggregate intrinsic value	$ 0
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	0	0	5,167	17,968
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0	0	0
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Oustanding number of options ending balance	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	0