Summary of Fair Value Warrant Derivative Liability and Related Common Shares (Detail) - USD ($)	Nov. 30, 2018	Aug. 31, 2018	May 31, 2018	Sep. 15, 2016
Derivative [Line Items]
Derivative liability	$ 2,826,919
Registered Direct Equity Offering \| Investor Warrants Issued with Registered Direct Equity Offering
Derivative [Line Items]
Shares indexed	7,733,334	7,733,334	7,733,334	7,733,334
Derivative liability	$ 1,789,066	$ 2,071,199	$ 1,323,732	$ 5,179,200

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant