Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive (Loss)/Income	Treasury Stock
Balance at Apr. 30, 2021	$ 266,384	$ 74	$ 273,431	$ 325,181	$ 73	$ (332,375)
Balance (in shares) at Apr. 30, 2021		74,222,000
Treasury stock, shares at Apr. 30, 2021						24,285,000
Stock-based compensation	1,452		1,452
Issuance of common stock under restricted stock unit awards, net of shares surrendered	(815)		(815)
Issuance of common stock under restricted stock unit awards, net of shares surrendered (in shares)		76,000
Repurchase of treasury stock	(40,000)					$ (40,000)
Repurchase of treasury stock, shares						1,967,000
Dividends issued	(3,844)			(3,844)
Net income	76,882			76,882
Balance at Jul. 31, 2021	300,059	$ 74	274,068	398,219	73	$ (372,375)
Balance (in shares) at Jul. 31, 2021		74,298,000
Treasury stock, shares at Jul. 31, 2021						26,252,000
Balance at Apr. 30, 2022	$ 360,514	$ 75	278,101	504,640	73	$ (422,375)
Balance (in shares) at Apr. 30, 2022	45,601,069	74,641,000
Treasury stock, shares at Apr. 30, 2022	29,040,370					29,040,000
Stock-based compensation	$ 1,177		1,177
Issuance of common stock under restricted stock unit awards, net of shares surrendered	(981)		(981)
Issuance of common stock under restricted stock unit awards, net of shares surrendered (in shares)		170,000
Dividends issued	(4,576)			(4,576)
Net income	3,312			3,312
Balance at Jul. 31, 2022	$ 359,446	$ 75	$ 278,297	$ 503,376	$ 73	$ (422,375)
Balance (in shares) at Jul. 31, 2022	45,770,597	74,811,000
Treasury stock, shares at Jul. 31, 2022	29,040,370					29,040,000