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Available For Sale Securities - Additional Information (Details)
3 Months Ended
Mar. 31, 2021
USD ($)
security
Mar. 31, 2020
USD ($)
Dec. 31, 2020
security
Investments, Debt and Equity Securities [Abstract]      
Realized gains (losses) on available for sale securities $ 0 $ 0  
Number of available-for-sale securities in a unrealized loss position | security 0   0
Available-for-sale securities, recognized credit losses during period $ 0 $ 0