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Short-Term Investments - Additional Information (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Cash Cash Equivalents And Available For Sale Securities [Abstract]        
Realized gains and losses on available-for-sale securities $ 0 $ 0 $ 0 $ 0
Contractual maturity date of investments     less than one year