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 ($) $ in Thousands |
12 Months Ended | 33 Months Ended | |
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May 31, 2020 |
May 31, 2019 |
Sep. 15, 2016 |
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| Derivative [Line Items] | |||
| Shares Indexed | 7,733,000 | 7,733,000 | |
| Fair value of warrants exercised | 7,733,000 | ||
| Change in fair value of derivative liability | $ 11,547 | $ (4,777) | |
| Fair value of warrants exercised | $ (11,949) | ||
| Derivative liability | $ 402 | $ 5,179 |
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- Definition Fair value of warrants exercised shares. No definition available.
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- Definition Gain (loss) on derivative instruments net pre taxes. No definition available.
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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 Amount of expense (income) related to adjustment to fair value of warrant liability. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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