Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Temporary equity number of shares issued	108,096,207	51,283,386
Temporary equity number of shares outstanding	108,096,207	51,283,386
Temporary equity liquidation preference	$ 193,968	$ 96,928
Common stock par value per share	$ 0.0001	$ 0.0001
Common stock number of shares authorised	146,000,000	76,000,000
Common stock number of shares issued	1,488,489	1,488,489
Common stock number of shares outstanding	1,488,489	1,488,489
Series A Redeemable Convertible Preferred Stock [Member]
Temporary equity par value per share	$ 0.0001	$ 0.0001
Temporary equity number of shares authorised	25,000,000	25,000,000
Temporary equity number of shares issued	25,000,000	25,000,000
Temporary equity number of shares outstanding	25,000,000	25,000,000
Temporary equity liquidation preference	$ 33,479	$ 32,482
Series B Redeemable Convertible Preferred Stock [Member]
Temporary equity par value per share	$ 0.0001	$ 0.0001
Temporary equity number of shares authorised	29,972,284	29,972,284
Temporary equity number of shares issued	29,972,284	26,283,386
Temporary equity number of shares outstanding	29,972,284	26,283,386
Temporary equity liquidation preference	$ 75,014	$ 64,446
Series C Redeemable Convertible Preferred Stock [Member]
Temporary equity par value per share	$ 0.0001	$ 0.0001
Temporary equity number of shares authorised	62,489,557
Temporary equity number of shares issued	53,123,923
Temporary equity number of shares outstanding	53,123,923
Temporary equity liquidation preference	$ 85,475

Face amount or stated value per share of common stock.

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