Equity and Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | |
|---|---|---|
Apr. 30, 2018 |
Apr. 30, 2017 |
|
| Equity [Abstract] | ||
| Quarterly dividends declared (in usd per share) | $ 0.5625 | |
| Compensation expense related to stock-based awards granted | $ 126 | $ 224 |