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Summary of Significant Accounting Policies (Tables)
9 Months Ended
Sep. 30, 2021
Accounting Policies [Abstract]  
Schedule of cash, cash equivalents, and restricted cash
   As of September 30, 
   2021   2020 
Cash and cash equivalents  $40,742   $165,905 
Restricted cash, current   
-
    50 
Restricted cash, non-current   745    
-
 
Total cash, cash equivalents, and restricted cash  $41,487   $165,955