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Marketable Securities and Fair Value Measurements - Additional Information (Details) - USD ($)
$ in Thousands
Mar. 31, 2020
Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Marketable securities $ 461,848 $ 459,256
Certificates of deposit    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Marketable securities 45,920 66,256
Certificates of deposit | Letter of Credit    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash balance held to secure letter of credit associated with lease and credit card $ 2,100 $ 1,500