Note 5 - Revenue From Contracts With Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Total revenue from contracts with customers	$ 8,347	$ 6,541	$ 19,348	$ 14,814
Transferred at Point in Time [Member]
Total revenue from contracts with customers	8,204	6,346	18,929	14,218
Transferred over Time [Member]
Total revenue from contracts with customers	143	195	419	596
Seamap [Member] | Transferred at Point in Time [Member]
Total revenue from contracts with customers	6,876	5,196	15,045	11,066
Seamap [Member] | Transferred over Time [Member]
Total revenue from contracts with customers	143	195	419	596
Klein [Member] | Transferred at Point in Time [Member]
Total revenue from contracts with customers	1,328	1,150	3,884	3,152
UNITED STATES
Total revenue from contracts with customers	967	282	1,545	2,068
Europe [Member]
Total revenue from contracts with customers	3,491	2,001	9,593	4,981
Middle East and Africa [Member]
Total revenue from contracts with customers	120	757	809	1,054
Asia Pacific [Member]
Total revenue from contracts with customers	3,667	3,342	6,560	5,841
Canada and Latin America [Member]
Total revenue from contracts with customers	$ 102	$ 159	$ 841	$ 870