Operating leases - Schedule of Components of Lease Expense (Detail) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended |
|---|---|---|
Jul. 31, 2019 |
Jul. 31, 2019 |
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| Leases [Abstract] | ||
| Operating lease cost | $ 206 | $ 412 |
| Short term lease cost | 3 | 14 |
| Total lease cost | $ 209 | $ 426 |
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- Definition Amount of lease cost recognized by lessee for lease contract. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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| X | ||||||||||
- Definition Amount of short-term lease cost, excluding expense for lease with term of one month or less. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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