Balance Sheet - Schedule of Inventories (Detail) - USD ($) $ in Thousands |
Apr. 30, 2018 |
Jan. 31, 2018 |
|---|---|---|
| Inventories: | ||
| Raw materials | $ 5,363 | $ 5,099 |
| Finished goods | 6,371 | 6,185 |
| Work in progress | 1,372 | 1,247 |
| Cost of inventories | 13,106 | 12,531 |
| Less allowance for obsolescence | (1,674) | (1,675) |
| Total inventories, net | $ 11,432 | $ 10,856 |