Stock-Based Compensation (Summary Of Stock Options) (Details) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Apr. 30, 2020 USD ($) $ / shares shares
Shares
Outstanding, beginning of the year (in shares) | shares	439
Granted (in shares) | shares	0
Option exercises (in shares) | shares	(11)
Forfeited or expired (in shares) | shares	0
Outstanding, end of the year (in shares) | shares	428
Exercisable, end of the year (in shares) | shares	337
Exercisable and expected to vest (in shares) | shares	423
Weighted-Average Exercise Price
Outstanding, beginning of the year (in usd per share) | $ / shares	$ 25.47
Granted (in usd per share) | $ / shares	0
Exercised (in usd per share) | $ / shares	16.89
Forfeited or expired (in usd per share) | $ / shares	0
Outstanding, end of the year (in usd per share) | $ / shares	25.68
Exercisable, end of the year (in usd per share) | $ / shares	24.58
Exercisable and expected to vest (in usd per share) | $ / shares	$ 25.63
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted-Average Remaining Contractual Term, Outstanding, end of the year	6 years
Weighted-Average Remaining Contractual Term, Exercisable, end of the year	5 years
Weighted-Average Remaining Contractual Term, Exercisable and expected to vest, years	6 years
Aggregate Intrinsic Value, Outstanding, end of the year | $	$ 13
Aggregate Intrinsic Value, Exercisable, end of the year | $	13
Aggregate Intrinsic Value, Exercisable and expected to vest | $	$ 13