Number of new stock classified as temporary equity repurchased during the period.

No definition available.

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- Definition

Value of new stock classified as temporary equity repurchased during the period.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Amount to be paid per share that is classified as temporary equity by entity upon redemption. 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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TEMPORARY EQUITY AND SHAREHOLDERS' DEFICIT (Details) (Imported) - USD ($) $ / shares in Units, $ in Thousands		9 Months Ended		12 Months Ended
	Feb. 04, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Temporary Equity [Line Items]
Stock-based compensation expense		$ 9,162	$ 9,990	$ 13,196	$ 14,974	$ 3,761
Convertible Preferred Stock
Temporary Equity [Line Items]
Shares repurchased	500,000
Repurchase price per share	$ 8.00				$ 8.00
Total purchase price	$ 4,000				$ 52,400
Stock-based compensation expense	$ 590				$ 6,600
Convertible Preferred Stock \| Common Stock [Member]
Temporary Equity [Line Items]
Shares repurchased					5,545,160
Series A convertible preferred stock
Temporary Equity [Line Items]
Shares repurchased					692,854
Series B convertible preferred stock
Temporary Equity [Line Items]
Shares repurchased					290,939
Series D convertible preferred stock
Temporary Equity [Line Items]
Shares repurchased					18,524