Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	COMMON STOCK	RETAINED EARNINGS	ACCUMULATED OTHER COMPREHENSIVE LOSS
Balance at beginning of period (shares) at Apr. 30, 2021		16,801,101
Balance at beginning of period at Apr. 30, 2021	$ 756,238	$ 362,524	$ 448,282	$ (54,568)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	2,981		2,981
Other comprehensive loss, net of tax	(200)			(200)
Stock-based compensation	1,177	$ 1,177
Exercise of stock-based compensation awards, net of amounts withheld for taxes (shares)		20,243
Exercise of stock-based compensation awards, net of amounts withheld for taxes	(1,033)	$ (1,033)
Stock repurchases (shares)		(299,781)
Stock repurchases		$ (5,874)
Stock repurchases	(25,000)		(19,126)
Employee benefit plan contributions (shares)		39,491
Employee benefit plan contributions	2,938	$ 2,938
Balance at end of period (shares) at Jul. 31, 2021		16,561,054
Balance at end of period at Jul. 31, 2021	737,101	$ 359,732	432,137	(54,768)
Balance at beginning of period (shares) at Apr. 30, 2022		16,570,619
Balance at beginning of period at Apr. 30, 2022	772,883	$ 363,224	399,434	10,225
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	20,070		20,070
Other comprehensive loss, net of tax	(1,278)			(1,278)
Stock-based compensation	1,635	$ 1,635
Exercise of stock-based compensation awards, net of amounts withheld for taxes (shares)		25,908
Exercise of stock-based compensation awards, net of amounts withheld for taxes	(772)	$ (772)
Balance at end of period (shares) at Jul. 31, 2022		16,596,527
Balance at end of period at Jul. 31, 2022	$ 792,538	$ 364,087	$ 419,504	$ 8,947