Accounting Policies and Basis of Presentation - Supplemental Cash Flow Information (Detail) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Apr. 30, 2016 |
Apr. 30, 2015 |
|
| Supplemental Cash Flow Information [Abstract] | ||
| Income taxes paid | $ 349 | $ 474 |
| Income tax refunds | (141) | (3,905) |
| Interest paid | 159 | 2,680 |
| Noncash investing and financing activities: | ||
| Exchange of 4.25% convertible notes for 8.0% convertible notes | 55,500 | |
| Accrued capital additions | $ 855 | $ 1,044 |