Warrants - Summary of Periodic Changes in Fair Value of Warrant Liability (Detail) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Warrant repurchases	$ (25,000)	$ (1,100,000)
Level 3 [Member] \| Common Stock Warrants [Member]
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Balance, January 1, 2018	65,000	3,400,869
Warrants settled upon exchange		(3,345,029)
Warrant repurchases	(25,000)
Changes in fair value	(30,000)	9,160
Balance, December 31, 2018	$ 10,000	$ 65,000

Derivative liabilities recognized as result of settlement agreement.

No definition available.

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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.

+ References

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.

+ References

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)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

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- Definition

The aggregate amount paid by the entity to reacquire the right to purchase equity shares at a predetermined price, usually issued together with corporate debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
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- Definition

Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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