Amendment agreement month and year.

No definition available.

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- Definition

Reclassification of warrant liability to additional paid-in capital.

+ References

No definition available.

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- Definition

Sale of stock.

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Stockholders' Equity - Warrants - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended	6 Months Ended
	Feb. 28, 2017	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Sale Of Stock [Line Items]
Change in fair value of warrant liability		$ 1,261,912	$ 433,392	$ (1,810,835)
July 2016 Financing [Member]
Sale Of Stock [Line Items]
Unregistered warrants to purchase of common stock	526,315
Conversion of stock, shares issued	211,860
Weighted average exercise price of warrants	$ 2.41
Reclassification of warrant liability to Additional Paid-in Capital	$ 1,400,000
Warrant Amendments [Member]
Sale Of Stock [Line Items]
Unregistered warrants to purchase of common stock			2,449,129
Reclassification of warrant liability to Additional Paid-in Capital			$ 3,300,000
Change in fair value of warrant liability			$ 433,000
Amendment date			2018-03