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Marketable Securities - Additional Information (Details) - Marketable Debt Securities [Member] - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]          
Impairments to marketable securities or reserves for credit losses $ 0 $ 0 $ 0 $ 0  
Marketable securities, Accrued interest 100,000   100,000   $ 100,000
U.S. Government Agency Bonds [Member]          
Debt Securities, Available-for-sale [Line Items]          
Debt securities considered to be an unrealized loss position         $ 0
U.S. Government Agency Bonds [Member] | Maximum [Member]          
Debt Securities, Available-for-sale [Line Items]          
Debt securities considered to be an unrealized loss position $ 100,000   $ 100,000