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Fair Value Measurements - Additional Information (Details) - USD ($)
$ in Millions
Sep. 30, 2020
Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Marketable securities remaining contractual term 1 year  
Recurring    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Money market fund, fair value   $ 77.4