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Marketable Securities - Summary of Amortized Cost, Gross Unrealized Gains and Losses and Estimated Fair Values (Details) - USD ($)
$ in Thousands
Mar. 31, 2022
Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost/​ Cost Basis $ 74,694 $ 118,065
Gross Unrealized Gains 9 7
Gross Unrealized Losses (175) (100)
Fair Value 74,528 117,972
U.S. Treasuries    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost/​ Cost Basis 0 0
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Fair Value 0 0
Corporate bonds    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost/​ Cost Basis 30,216 57,460
Gross Unrealized Gains 2 0
Gross Unrealized Losses (114) (72)
Fair Value 30,104 57,388
Municipal bonds    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost/​ Cost Basis 21,990 28,325
Gross Unrealized Gains 5 5
Gross Unrealized Losses (40) (10)
Fair Value 21,955 28,320
Commercial paper    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost/​ Cost Basis 19,997 19,989
Gross Unrealized Gains 0 0
Gross Unrealized Losses 0 0
Fair Value 19,997 19,989
Foreign governments    
Debt Securities, Available-for-sale [Line Items]    
Amortized Cost/​ Cost Basis 2,491 12,291
Gross Unrealized Gains 2 2
Gross Unrealized Losses (21) (18)
Fair Value $ 2,472 $ 12,275