Fair Value of Financial Assets (Details) - USD ($)
$ in Thousands
6 Months Ended
Jun. 30, 2020
Dec. 31, 2019
Fair Value of Financial Assets    
Transfers from Level 1 to Level 2 $ 0  
Transfers from Level 2 to Level 1 0  
Transfers from into Level 3 0  
Transfers from out of Level 3 0  
Recurring    
Fair Value of Financial Assets    
Total 35,384 $ 35,132
Recurring | Money market funds    
Fair Value of Financial Assets    
Cash equivalents 35,384 35,132
Recurring | Level 1    
Fair Value of Financial Assets    
Total 35,384 35,132
Recurring | Level 1 | Money market funds    
Fair Value of Financial Assets    
Cash equivalents $ 35,384 $ 35,132