Warrants issued to purchase common stock.

No definition available.

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- Definition

The value as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the share warrants plan.

+ References

No definition available.

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- Definition

As of the balance sheet date, the number of warrants into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

+ References

No definition available.

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- Definition

It represents value of warrant liabilities.

+ References

No definition available.

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- Definition

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

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-Section S99
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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.

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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.

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No definition available.

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- Definition

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

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- Definition

The cash inflow from the additional capital contribution to the entity.

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

Number of new stock issued during the period.

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- Definition

Fair value portion of warrants not settleable in cash classified as equity.

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Stock Purchase Warrants (Details Textual) - USD ($)	1 Months Ended		3 Months Ended		9 Months Ended
Stock Purchase Warrants (Details Textual) - USD ($)	Nov. 18, 2016	Oct. 10, 2014	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 26, 2017
Equity, Class of Treasury Stock [Line Items]
Warrants Not Settleable in Cash, Fair Value Disclosure								$ 9,000
Change in fair value of warrant liability			$ (626,000)	$ 5,092,000	$ (4,064,000)	$ (2,157,000)
Warrant liabilities			19,000		19,000		$ 4,083,000
Warrant [Member]
Equity, Class of Treasury Stock [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Warrants Exercisable Number								714
Stock Warrants [Member]
Equity, Class of Treasury Stock [Line Items]
Sale of Stock, Price Per Share		$ 51.45
Change in fair value of warrant liability		$ 7,400,000	21,000	1,000,000	415,000	200,000
Proceeds from Issuance of Common Stock		$ 19,100,000
Sale of Stock, Number of Shares Issued in Transaction		401,703
Issuance Of Warrants To Purchase Of Common Stock		0.5
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number		61.25
Share Based Compensation Arrangement By Share Based Payment Award Warrants Vested and Expected To Vest Outstanding Number		200,852
Warrant liabilities				2,000,000		2,000,000
IPO [Member]
Equity, Class of Treasury Stock [Line Items]
Sale of Stock, Price Per Share	$ 35
Stock Issued During Period, Shares, New Issues	714,286
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	1,428,571,000,000
Warrants Not Settleable in Cash, Fair Value Disclosure	$ 15,700,000		19,000	10,700,000	19,000	10,700,000
Change in fair value of warrant liability			$ 605,000	$ 4,100,000	$ 3,600,000	$ 2,000,000
IPO [Member] \| Series A [Member]
Equity, Class of Treasury Stock [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 50.05
IPO [Member] \| Series B [Member]
Equity, Class of Treasury Stock [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 60.20