Condensed Consolidated Statements of Income/(Loss) and Comprehensive Income/(Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Income Statement [Abstract]
Net sales	$ 230,479	$ 248,729	$ 505,088	$ 478,614
Cost of sales	128,484	147,656	273,151	285,117
Gross profit	101,995	101,073	231,937	193,497
Operating expenses:
Research and development	1,744	1,855	3,552	3,761
Selling, marketing, and distribution	11,423	11,614	22,057	21,609
General and administrative	23,436	23,224	41,049	45,007
Total operating expenses	36,603	36,693	66,658	70,377
Operating income from continuing operations	65,392	64,380	165,279	123,120
Other income/(expense), net:
Other income/(expense), net	833	693	1,493	760
Interest expense, net	(466)	(1,490)	(1,011)	(2,806)
Total other income/(expense), net	367	(797)	482	(2,046)
Income from continuing operations before income taxes	65,759	63,583	165,761	121,074
Income tax expense	14,824	14,465	37,944	28,657
Income from continuing operations	50,935	49,118	127,817	92,417
Discontinued operations:
Income from discontinued operations, net of tax		3,123		8,209
Net income	$ 50,935	$ 52,241	$ 127,817	$ 100,626
Net income per share:
Basic - continuing operations	$ 1.06	$ 0.88	$ 2.65	$ 1.66
Basic - net income	1.06	0.93	2.65	1.81
Diluted - continuing operations	1.05	0.87	2.63	1.64
Diluted - net income	$ 1.05	$ 0.92	$ 2.63	$ 1.78
Weighted average number of common shares outstanding:
Basic	48,147	55,914	48,270	55,691
Diluted	48,692	56,531	48,524	56,475