Industry Segments - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2023	Oct. 31, 2022
Segment Reporting Information [Line Items]
Revenues	$ 25,690	$ 27,279	$ 51,591	$ 54,060
Operating income\(loss)	1,229	2,550	2,621	4,892
Capital expenditures	56	1,134	521	2,706
Depreciation and amortization	1,277	833	2,007	1,601
Earnings\(loss) before income taxes	652	2,405	3,930	4,866
Supply Chain Management
Segment Reporting Information [Line Items]
Revenues	25,188	26,752	50,549	52,934
Operating income\(loss)	5,835	7,646	12,277	14,825
Capital expenditures	37	151	387	1,590
Depreciation and amortization	1,102	714	1,653	1,367
Earnings\(loss) before income taxes	5,855	7,572	12,543	14,601
Other
Segment Reporting Information [Line Items]
Revenues	502	527	1,042	1,126
Operating income\(loss)	(4,606)	(5,096)	(9,656)	(9,933)
Capital expenditures	19	983	134	1,116
Depreciation and amortization	175	119	354	234
Earnings\(loss) before income taxes	$ (5,203)	$ (5,167)	$ (8,613)	$ (9,735)