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Number of outstanding stock option.

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Number of warrants or rights outstanding.

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Total number of shares of other common stock instruments held by shareholders, such as exchangeable shares. May be all or portion of the number of common shares authorized.

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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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Number of common shares issuable upon conversion of preferred stock.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Number of options outstanding, including both vested and non-vested options.

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Number of non-vested options outstanding.

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Losses Per Share (Details) - shares	1 Months Ended	9 Months Ended		12 Months Ended
Losses Per Share (Details) - shares	Dec. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2019
Losses Per Share (Details) [Line Items]
Number of outstanding stock option	15,274,639			8,027,354
Warrants outstanding	189,395			189,395
Outstanding stock options shares		15,642,133	9,057,354
unvested options shares		664,938
Preferred stock outstanding		58,554,536
Common stock converted shares		189,395	189,395
Convertible preferred shares outstanding		60,121,015	60,121,015
Warrant [Member]
Losses Per Share (Details) [Line Items]
Preferred stock outstanding		172,759	172,759
Common stock outstanding		114,162	213,162
Convertible Preferred Shares [Member]
Losses Per Share (Details) [Line Items]
Number of outstanding stock option	58,554,536			50,588,630