Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Redeemable convertible preferred stock:
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Redeemable convertible preferred stock, authorized (in shares)	4,471,316	4,471,316
Redeemable convertible preferred stock, issued (in shares)	4,471,316	4,471,316
Redeemable convertible preferred stock, outstanding (in shares)	4,471,316	4,471,316
Redeemable convertible preferred stock, liquidation preference	$ 5,768	$ 5,768
Stockholders' deficit:
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	36,525,154	31,525,154
Common stock, issued (in shares)	20,607,851	18,486,989
Common stock, outstanding (in shares)	20,607,851	18,486,989

Face amount or stated value per share of common stock.

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