Industry Segments - Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Jul. 31, 2020	Jul. 31, 2019
Segment Reporting Information [Line Items]
Revenues	$ 27,278	$ 27,383
Operating income (loss)	885	797
Capital expenditures	118	110
Capitalized software	245	1,285
Depreciation and amortization	1,680	2,245
Earnings (loss) before income taxes	2,217	1,322
Supply Chain Management
Segment Reporting Information [Line Items]
Revenues	21,736	22,347
Operating income (loss)	4,105	3,851
Capital expenditures	39	31
Capitalized software	245	1,285
Depreciation and amortization	1,586	2,151
Earnings (loss) before income taxes	4,376	4,036
IT Consulting
Segment Reporting Information [Line Items]
Revenues	5,026	4,378
Operating income (loss)	106	178
Capital expenditures	0	0
Capitalized software	0	0
Depreciation and amortization	1	2
Earnings (loss) before income taxes	104	178
Other
Segment Reporting Information [Line Items]
Revenues	516	658
Operating income (loss)	(3,326)	(3,232)
Capital expenditures	79	79
Capitalized software	0	0
Depreciation and amortization	93	92
Earnings (loss) before income taxes	$ (2,263)	$ (2,892)