Industry Segments - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Segment Reporting Information [Line Items]
Revenues	$ 32,422	$ 27,683	$ 92,904	$ 82,842
Operating income\(loss)	3,239	935	7,699	2,451
Capital expenditures	222	298	837	461
Capitalized software	0	233	0	604
Depreciation and amortization	1,000	1,247	3,170	4,441
Earnings\(loss) before income taxes	3,331	2,367	9,158	5,173
Supply Chain Management
Segment Reporting Information [Line Items]
Revenues	26,061	22,646	75,692	66,679
Operating income\(loss)	7,458	4,713	19,531	12,800
Capital expenditures	57	152	672	236
Capitalized software	0	233	0	604
Depreciation and amortization	907	1,149	2,889	4,150
Earnings\(loss) before income taxes	7,458	4,803	19,377	13,023
IT Consulting
Segment Reporting Information [Line Items]
Revenues	5,842	4,543	15,544	14,602
Operating income\(loss)	506	83	1,005	292
Capital expenditures	0	0	0	0
Capitalized software	0	0	0	0
Depreciation and amortization	0	0	0	2
Earnings\(loss) before income taxes	506	83	1,005	290
Other
Segment Reporting Information [Line Items]
Revenues	519	494	1,668	1,561
Operating income\(loss)	(4,725)	(3,861)	(12,837)	(10,641)
Capital expenditures	165	146	165	225
Capitalized software	0	0	0	0
Depreciation and amortization	93	98	281	289
Earnings\(loss) before income taxes	$ (4,633)	$ (2,519)	$ (11,224)	$ (8,140)