Condensed consolidated balance sheets (Parentheticals) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Redeemable convertible preferred stock, authorized (in shares)	0	161,455,689
Redeemable convertible preferred stock, issued (in shares)	0	133,021,640
Redeemable convertible preferred stock, outstanding (in shares)	0	133,021,640
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	10,000,000	0
Preferred stock, issued (in shares)	0	0
Common Class A
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	210,000,000	35,000,000
Common stock, issued (in shares)	34,449,154	612,850
Common stock, outstanding (in shares)	34,449,154	612,850
Common Class B
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	10,000,000	0
Common stock, issued (in shares)	6,903,379	0
Common stock, outstanding (in shares)	6,903,379	0

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

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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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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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