Class Of Warrant Or Right, Warrant Term

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- Definition

Class of warrant or right warrants expiration date.

+ References

No definition available.

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- Definition

Class of warrant or right warrants expiration month and year.

+ References

No definition available.

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- Definition

Class of Warrant Or Right, Liquidated Damages Amount, Percent of Volume Weighted Average Price

+ References

No definition available.

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- Definition

Ownership interest, percentage of voting rights 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))
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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

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- Definition

Number of warrants or rights outstanding.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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-Section S99
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-Subparagraph (SX 210.5-02(29))
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Publisher FASB
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-Topic 718
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-Paragraph 2
-Subparagraph (i)
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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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-Name Accounting Standards Codification
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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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Stockholders' Equity - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Oct. 31, 2015	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend yield		0.00%	0.00%	0.00%	0.00%
Weighted average grant date fair value per option granted (in dollars per share)				$ 1.95	$ 1.18
Stock options outstanding, intrinsic value		$ 700,000		$ 700,000
Number of shares available for issuance under the plan on the first day of each year		79,560,274		79,560,274		44,658,054
Series D Warrants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding (in shares)	270,270
Number of common stock purchased upon issuance of warrants	540,540
Exercise price of warrants (in dollars per share)	$ 8.75
Warrants term	5 years
Warrants expiration date	Oct. 15, 2020
Liquidated damages amount percent of VWAP (percent)	1.00%
Warrants to Purchase Stock [Member] \| 2010 and 2012 Convertible Promissory Notes [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding (in shares)		102,070		102,070
Exercise price of warrants (in dollars per share)		$ 24.35		$ 24.35
Warrants term				10 years
Warrants expiration period				2024-11
Underwriter [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding (in shares)		16,500		16,500
Exercise price of warrants (in dollars per share)		$ 35.70		$ 35.70
Warrants term				10 years
Warrants expiration period				2024-11
Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant		27,967		27,967
Percentage of outstanding stock maximum				1.00%
Number of shares available for issuance under the plan on the first day of each year		55,936		55,936
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Ownership interest of voting rights of all classes of stock (percent)		10.00%		10.00%
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
Number of shares available for grant		1,818,603		1,818,603
Income tax benefits recognized from stock-based compensation		$ 0	$ 0	$ 0	$ 0
Number of options granted		452,650	114,142	452,650	578,142
Future stock-based compensation for unvested employee options granted and outstanding		$ 1,600,000		$ 1,600,000
Future stock-based compensation, requisite service period				2 years 8 months 12 days
Stock Options [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of fair market value				110.00%
Stock Options [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual term of option				10 years
ISOs [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual term of option				5 years
Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period				4 years
Future stock-based compensation for unvested employee options granted and outstanding		$ 2,000,000		$ 2,000,000
Stock units granted		16,461	16,708	703,718	38,123
Vesting percentage				100.00%
Weighted average grant-date fair value of all restricted stock units granted				$ 3.81	$ 2.42
Fair value of restricted stock units vested				$ 100,000	$ 92,000
Weighted average remaining vesting period				3 years 6 months