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Fair Value Measurement - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 6 Months Ended
Dec. 31, 2019
Apr. 30, 2020
Jun. 30, 2020
Jun. 30, 2019
Apr. 01, 2020
Fair Value Disclosures [Line Items]          
Proceeds from convertible loan notes     $ 10,000 $ 0  
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]          
Fair Value Disclosures [Line Items]          
Proceeds from convertible loan notes   $ 10,000      
Series B Redeemable Convertible Preferred Stock [Member]          
Fair Value Disclosures [Line Items]          
Fair value per share     $ 2.20    
Exercise date of preferred stock tranche right Jan. 14, 2020        
Series C Redeemable Convertible Preferred Stock [Member]          
Fair Value Disclosures [Line Items]          
Debt instrument conversion price         $ 1.6016
Series C Redeemable Convertible Preferred Stock [Member] | Fair Value, Inputs, Level 3 [Member]          
Fair Value Disclosures [Line Items]          
Change in fair value of convertible notes     $ 100