Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Apr. 30, 2018 |
Apr. 30, 2017 |
Jan. 31, 2018 |
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| Income Tax Disclosure [Abstract] | |||
| Income tax (benefit) provision | $ (494) | $ 269 | |
| Reversal of tax reserves for uncertain tax positions due to the expiration of statute of limitations | $ 100 | ||
| Corporate tax rate | 21.00% | 35.00% | |
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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