Segment Reporting - Financial Information by Business Segment (Revenues) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2019	Apr. 30, 2018
Segment Reporting Information [Line Items]
Revenues	$ 9,857	$ 7,613
Operating loss	(2,456)	(5,572)
Loss before taxes	(2,360)	(5,468)
Operating Segments | Marine Technology Products
Segment Reporting Information [Line Items]
Revenues	5,982	3,708
Operating loss	(1,161)	(2,374)
Loss before taxes	(1,161)	(2,348)
Operating Segments | Equipment Leasing
Segment Reporting Information [Line Items]
Revenues	3,935	4,047
Operating loss	(389)	(2,293)
Loss before taxes	(293)	(2,215)
Corporate expenses
Segment Reporting Information [Line Items]
Revenues	0	0
Operating loss	(906)	(905)
Loss before taxes	(906)	(905)
Eliminations
Segment Reporting Information [Line Items]
Revenues	(60)	(142)
Operating loss	0	0
Loss before taxes	$ 0	$ 0