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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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Value of the difference between preference in liquidation and the par or stated values of the preferred shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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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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The aggregate liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. 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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No definition available.

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- Definition

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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Carrying amount of the par value of temporary equity outstanding. 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. 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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CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Mar. 28, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Redeemable convertible preferred stock, authorized (in shares)				9,898,400
Preferred stock, par value (in USD per share)	$ 0.00001				$ 0.00001				$ 0.00001
Preferred stock, authorized (in shares)	100,000,000				9,898,400				9,898,400
Common stock, par value (in USD per share)	$ 0.00001				$ 0.00001				$ 0.00001
Common stock, authorized (in shares)	0				300,000,000				300,000,000
Common stock, issued (in shares)	0				95,206,893				94,592,700
Common stock, outstanding (in shares)	0				95,050,041				94,592,700
Series A redeemable convertible preferred stock
Redeemable convertible preferred stock, par value (in USD per share)	$ 0.00001				$ 0.00001				$ 0.00001
Redeemable convertible preferred stock, authorized (in shares)	0			3,379,400	3,379,400
Redeemable convertible preferred stock, issued (in shares)	0				3,379,400				3,379,400
Redeemable convertible preferred stock, outstanding (in shares)	0	0	0		3,379,400	3,379,400	3,379,400	3,379,400	3,379,400	3,379,400
Redeemable convertible preferred stock, liquidation value					$ 8,000				$ 8,000
Series A-1 redeemable convertible preferred stock
Redeemable convertible preferred stock, par value (in USD per share)	$ 0.00001				$ 0.00001				$ 0.00001
Redeemable convertible preferred stock, authorized (in shares)	0			1,837,600	1,837,600				1,837,600
Redeemable convertible preferred stock, issued (in shares)	0				1,837,600				1,837,600
Redeemable convertible preferred stock, outstanding (in shares)	0	0	0		1,837,600	1,837,600	1,837,600	1,837,600	1,837,600	0
Redeemable convertible preferred stock, liquidation value					$ 5,000				$ 5,000
Series B convertible preferred stock
Redeemable convertible preferred stock, authorized (in shares)				4,681,400
Preferred stock, par value (in USD per share)	$ 0.00001				$ 0.00001				$ 0.00001
Preferred stock, authorized (in shares)	0				4,681,400				4,681,400
Preferred stock, issued (in shares)	0				4,681,400				4,681,400
Preferred stock, outstanding (in shares)	0				4,681,400				4,681,400
Preferred stock, liquidation value					$ 24,000				$ 24,000