Industry Segments - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2021	Jul. 31, 2020
Segment Reporting Information [Line Items]
Revenues	$ 29,271	$ 27,278
Operating income (loss)	1,773	885
Capital expenditures	302	118
Capitalized software	0	245
Depreciation and amortization	1,131	1,680
Earnings (loss) before income taxes	2,210	2,217
Supply Chain Management
Segment Reporting Information [Line Items]
Revenues	24,251	21,736
Operating income (loss)	5,356	4,105
Capital expenditures	302	39
Capitalized software	0	245
Depreciation and amortization	1,034	1,586
Earnings (loss) before income taxes	5,261	4,376
IT Consulting
Segment Reporting Information [Line Items]
Revenues	4,476	5,026
Operating income (loss)	163	106
Capital expenditures	0	0
Capitalized software	0	0
Depreciation and amortization	0	1
Earnings (loss) before income taxes	163	104
Other
Segment Reporting Information [Line Items]
Revenues	544	516
Operating income (loss)	(3,746)	(3,326)
Capital expenditures	0	79
Capitalized software	0	0
Depreciation and amortization	97	93
Earnings (loss) before income taxes	$ (3,214)	$ (2,263)