The value pertaining to fair value of warrant liability.

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Warrants issued to purchase common stock.

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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.

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Represents the warrant term.

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

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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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The number of shares converted 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.

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

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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

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Stock Warrants - Additional Information (Details) - USD ($)					1 Months Ended	6 Months Ended
	Oct. 15, 2018	Oct. 15, 2018	Oct. 10, 2018	Oct. 10, 2014	Nov. 18, 2016	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Oct. 31, 2018	Dec. 26, 2017
Equity, Class of Treasury Stock
Proceeds from Issuance or Sale of Equity		$ 18,600,000
Warrants Not Settleable in Cash, Fair Value Disclosure										$ 9,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	13,672,173	13,672,173
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 1.38	$ 1.38							$ 1.38
Class A [Member]
Equity, Class of Treasury Stock
Stock Issued During Period, Shares, New Issues	2,520,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number				61.25
Preferred Stock Conversion Price Per Share	$ 1.15	$ 1.15
Class B [Member]
Equity, Class of Treasury Stock
Stock Issued During Period, Shares, New Issues		15,723
Series B Preferred Stock [Member]
Equity, Class of Treasury Stock
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	13,672,173	13,672,173
Stock Issued During Period, Value, Issued for Services		$ 1,000
Preferred Stock, Par or Stated Value Per Share	$ 1,000	$ 1,000				$ 1,000	$ 1,000
Conversion of Stock, Shares Converted		13,672,173				10,198
IPO [Member]
Equity, Class of Treasury Stock
Warrants Not Settleable in Cash, Fair Value Disclosure					$ 15,700,000	$ 100,000		$ 100,000
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
Sale of Stock, Price Per Share				$ 1.47	$ 35.00
IPO [Member] \| Series A [Member]
Equity, Class of Treasury Stock
Class of Warrant or Right, Exercise Price of Warrants or Rights					50.05
IPO [Member] \| Series B [Member]
Equity, Class of Treasury Stock
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 60.20
Over-Allotment Option [Member]
Equity, Class of Treasury Stock
Stock Issued During Period, Shares, New Issues		2,428,825	2,428,825
Issuance Of Warrants To Purchase Of Common Stock	1,807,826	1,807,826
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	2,428,825	2,428,825	2,428,825
Underwritten Public Offering [Member] \| October 2018 Warrants [Member]
Equity, Class of Treasury Stock
Warrant Term		5 years
Series A Warrants [Member]
Equity, Class of Treasury Stock
Proceeds from Issuance of Common Stock				$ 19,100,000
Sale of Stock, Number of Shares Issued in Transaction				14,059,616
Issuance Of Warrants To Purchase Of Common Stock				0.50
Share Based Compensation Arrangement By Share Based Payment Award Warrants Vested and Expected To Vest Outstanding Number				200,852
Fair Value of Warrant Liability						$ 0		$ 0
Fair Value Adjustment of Warrants				$ 7,400,000
Warrant [Member]
Equity, Class of Treasury Stock
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Warrants Exercisable Number										714
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	13,672,173	13,672,173