Represents the number of votes per common stock.

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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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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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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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Number of new stock issued during the period.

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- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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- Definition

Per share amount of par value or stated value of stock classified as temporary equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable.

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The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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STOCKHOLDERS' EQUITY - Authorized, issued and outstanding and Common Stock (Details) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended	9 Months Ended
	Feb. 28, 2017 USD ($) Vote shares	Oct. 31, 2016 USD ($)	Jun. 30, 2019 USD ($) $ / shares shares	Sep. 30, 2019 Vote $ / shares shares	May 16, 2019 shares	Mar. 31, 2019 $ / shares shares	Dec. 31, 2018 $ / shares shares	Sep. 30, 2018 $ / shares shares	Jun. 30, 2018 $ / shares shares	Mar. 31, 2018 $ / shares shares	Dec. 31, 2017 $ / shares shares
STOCKHOLDERS' EQUITY
Common Stock, authorized (in shares)				100,000,000			20,441,982				11,049,720
Common Stock, par value (in dollars per share) \| $ / shares				$ 0.0001			$ 0.0001				$ 0.0001
Convertible preferred stock, authorized (in shares)							10,883,950				3,535,910
Convertible preferred stock, par value (in dollars per share) \| $ / shares							$ 0.0001
Common Stock, issued (in shares)				17,134,190			5,513,531				5,458,450
Common stock, outstanding (in shares)				17,134,190			5,513,531				5,458,450
Convertible preferred stock, issued (in shares)							7,095,746				3,093,898
Convertible preferred stock, outstanding (in shares)				0	0		7,095,746
Fair value of stock issued \| $			$ 34,618
Series A Convertible Preferred Stock
STOCKHOLDERS' EQUITY
Convertible preferred stock, authorized (in shares)				0			3,093,898				3,535,910
Convertible preferred stock, par value (in dollars per share) \| $ / shares				$ 0.0001			$ 0.0001				$ 0.0001
Convertible preferred stock, issued (in shares)				0			3,093,898				3,093,898
Convertible preferred stock, outstanding (in shares)				0		3,093,898	3,093,898	3,093,898	3,093,898	3,093,898	3,093,898
Series B Convertible Preferred Stock
STOCKHOLDERS' EQUITY
Convertible preferred stock, authorized (in shares)				0			7,790,052				0
Convertible preferred stock, par value (in dollars per share) \| $ / shares				$ 0.0001			$ 0.0001				$ 0.0001
Convertible preferred stock, issued (in shares)				0			4,001,848				0
Convertible preferred stock, outstanding (in shares)				0		4,444,773	4,001,848				0
Common Stock Par value $0.0001
STOCKHOLDERS' EQUITY
Common Stock, par value (in dollars per share) \| $ / shares			$ 0.0001	$ 0.0001		$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Shares issued (in shares)			4,000,000
Fair value of stock issued \| $			$ 1
Number of votes per common stock \| Vote	1			1
Columbia University \| 2016 license agreement
STOCKHOLDERS' EQUITY
Shares issued (in shares)	486,077
Fair value of stock issued \| $	$ 500	$ 500