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Fair Value Measurements - (Details) - USD ($)
$ in Thousands
Mar. 31, 2020
Dec. 31, 2019
Mar. 31, 2019
Fair value of the Company’s financial assets      
Marketable securities $ 293,191 $ 300,514  
Assets transferred from level 1 to level 2 0   $ 0
Assets transferred from level 2 to level 1 0   $ 0
Fair Value      
Fair value of the Company’s financial assets      
Total financial assets 308,349 319,855  
Fair Value | Quoted Prices in Active Markets (Level 1)      
Fair value of the Company’s financial assets      
Total financial assets 15,158 19,341  
Fair Value | Significant Other Observable Inputs (Level 2)      
Fair value of the Company’s financial assets      
Total financial assets 293,191 300,514  
Money market funds (cash equivalents) | Fair Value      
Fair value of the Company’s financial assets      
Money market funds (cash equivalents) 15,158 19,341  
Money market funds (cash equivalents) | Fair Value | Quoted Prices in Active Markets (Level 1)      
Fair value of the Company’s financial assets      
Money market funds (cash equivalents) 15,158 19,341  
U.S. treasury securities | Fair Value      
Fair value of the Company’s financial assets      
Marketable securities   4,991  
U.S. treasury securities | Fair Value | Significant Other Observable Inputs (Level 2)      
Fair value of the Company’s financial assets      
Marketable securities   4,991  
Agency bonds | Fair Value      
Fair value of the Company’s financial assets      
Marketable securities 35,800 24,451  
Agency bonds | Fair Value | Significant Other Observable Inputs (Level 2)      
Fair value of the Company’s financial assets      
Marketable securities 35,800 24,451  
Corporate bonds | Fair Value      
Fair value of the Company’s financial assets      
Marketable securities 257,391 271,072  
Corporate bonds | Fair Value | Significant Other Observable Inputs (Level 2)      
Fair value of the Company’s financial assets      
Marketable securities $ 257,391 $ 271,072