Summary of Fair Value Warrant Derivative Liability and Related Common Shares (Detail) - Registered Direct Equity Offering - Investor Warrants Issued with Registered Direct Equity Offering - USD ($) |
May 31, 2019 |
May 31, 2018 |
Sep. 15, 2016 |
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| Derivative [Line Items] | |||
| Shares indexed | 7,733,334 | 7,733,334 | 7,333,334 |
| Derivative liability | $ 402,132 | $ 1,323,732 | $ 5,179,200 |
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The number of issuer's shares to which the forward contract is indexed. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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