Quarterly report pursuant to Section 13 or 15(d)

Marketable securities - Available-for-sale debt securities (Details)

v3.21.2
Marketable securities - Available-for-sale debt securities (Details)
$ in Thousands
6 Months Ended
Jun. 30, 2021
USD ($)
Debt Securities  
Marketable securities  
Amortized cost $ 234,925
Gross unrealized gains 145
Gross unrealized losses (153)
Aggregate estimated fair value 234,917
Corporate Debt Securities Maturity Period Less Than Three Months | Debt Securities  
Marketable securities  
Amortized cost 28,564
Gross unrealized gains 29
Aggregate estimated fair value 28,593
Corporate Debt Securities Maturity Period Three Months To One Year  
Marketable securities  
Amortized cost 125,824
Gross unrealized gains 116
Gross unrealized losses (11)
Aggregate estimated fair value 125,929
Corporate Debt Securities Maturity Period One Year To Two Years | Debt Securities  
Marketable securities  
Amortized cost 80,537
Gross unrealized losses (142)
Aggregate estimated fair value $ 80,395
Minimum | Corporate Debt Securities Maturity Period One Year or Less | Debt Securities  
Marketable securities  
Available For Sale Securities Debt Maturity Period 3 months
Minimum | Corporate Debt Securities Maturity Period One Year To Two Years | Debt Securities  
Marketable securities  
Available For Sale Securities Debt Maturity Period 1 year
Maximum | Corporate Debt Securities Maturity Period Less Than Three Months | Debt Securities  
Marketable securities  
Available For Sale Securities Debt Maturity Period 3 months
Maximum | Corporate Debt Securities Maturity Period One Year or Less | Debt Securities  
Marketable securities  
Available For Sale Securities Debt Maturity Period 1 year
Maximum | Corporate Debt Securities Maturity Period One Year To Two Years | Debt Securities  
Marketable securities  
Available For Sale Securities Debt Maturity Period 2 years