Industry Segments - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2024	Jan. 31, 2023	Jan. 31, 2024	Jan. 31, 2023
Segment Reporting Information [Line Items]
Revenues	$ 25,536	$ 27,427	$ 77,127	$ 81,487
Operating income\(loss)	815	2,745	3,436	7,637
Capital expenditures	68	949	589	3,655
Depreciation and amortization	1,634	788	3,641	2,389
Earnings\(loss) before income taxes	5,232	4,079	9,162	8,945
Supply Chain Management
Segment Reporting Information [Line Items]
Revenues	25,009	26,952	75,558	79,886
Operating income\(loss)	6,119	7,763	18,396	22,587
Capital expenditures	21	14	434	1,604
Depreciation and amortization	1,462	675	3,115	2,042
Earnings\(loss) before income taxes	7,810	8,094	20,353	22,695
Other
Segment Reporting Information [Line Items]
Revenues	527	475	1,569	1,601
Operating income\(loss)	(5,304)	(5,018)	(14,960)	(14,950)
Capital expenditures	47	935	155	2,051
Depreciation and amortization	172	113	526	347
Earnings\(loss) before income taxes	$ (2,578)	$ (4,015)	$ (11,191)	$ (13,750)