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Available-for-Sale Securities - Additional Information (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Mar. 31, 2020
Jun. 30, 2021
Jun. 30, 2020
Investments Debt And Equity Securities [Abstract]          
Available-for-sale securities investments, gross unrealized losses $ 0     $ 0  
Unrealized gain (loss) on short-term investments $ 0 $ (26,136) $ 47,697 $ 0 $ 21,561