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Available For Sale Securities - Additional Information (Details)
3 Months Ended 9 Months Ended
Sep. 30, 2020
USD ($)
Sep. 30, 2019
USD ($)
Sep. 30, 2020
USD ($)
Sep. 30, 2019
USD ($)
Dec. 31, 2019
security
Investments, Debt and Equity Securities [Abstract]          
Realized gains (losses) on available for sale securities $ 0 $ 0 $ 0 $ 0  
Number of available-for-sale securities in a unrealized loss position | security         0
Available-for-sale securities, recognized credit losses during period $ 0   $ 0