Quarterly report pursuant to Section 13 or 15(d)

Fair value measurements (Details)

v3.21.1
Fair value measurements (Details) - USD ($)
$ in Thousands
Mar. 31, 2021
Dec. 31, 2020
Marketable securities:    
Available-for-sale securities, Debt Securities, Current, Total $ 285,512 $ 311,335
Recurring basis    
Marketable securities:    
Available-for-sale securities, Debt Securities, Current, Total 285,512  
Recurring basis | Corporate debt securities    
Marketable securities:    
Available-for-sale securities, Debt Securities, Current, Total 279,507  
Recurring basis | Agency bonds    
Marketable securities:    
Available-for-sale securities, Debt Securities, Current, Total 6,005  
Recurring basis | Level 1    
Marketable securities:    
Available-for-sale securities, Debt Securities, Current, Total 279,507  
Recurring basis | Level 1 | Corporate debt securities    
Marketable securities:    
Available-for-sale securities, Debt Securities, Current, Total 279,507  
Recurring basis | Level 2    
Marketable securities:    
Available-for-sale securities, Debt Securities, Current, Total 6,005  
Recurring basis | Level 2 | Agency bonds    
Marketable securities:    
Available-for-sale securities, Debt Securities, Current, Total $ 6,005