Warrants - Summary of Periodic Changes in Fair Value of Warrant Liability (Detail) - USD ($)	9 Months Ended
Sep. 30, 2019	Sep. 30, 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, 2019	65,000
Changes in fair value	(30,000)
Warrant repurchases	(25,000)
Balance, September 30, 2019	$ 10,000

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

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)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Paragraph 15
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Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

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