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Short-Term Investments - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Cash Cash Equivalents And Available For Sale Securities [Abstract]    
Short-term investments $ 0 $ 208,614,000
Realized gains and losses on available-for-sale securities $ 0 $ 0
Contractual maturity date of investments Less than one year