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Financial Instruments - Summary of Cash and Cash Equivalents, Money Market Funds and Short-term Investments by Significant Investment Category (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]    
Adjusted Cost $ 183,958 $ 263,729
Unrealized Gains 1 15
Unrealized Losses (202) (47)
Market Value 183,757 263,697
Level 1 | Money Market Funds    
Debt Securities, Available-for-sale [Line Items]    
Adjusted Cost 15,329 27,686
Unrealized Gains 0 0
Unrealized Losses 0 0
Market Value 15,329 27,686
Level 2 | Corporate debt securities included in cash and cash equivalents and short-term investments    
Debt Securities, Available-for-sale [Line Items]    
Adjusted Cost 163,626 118,759
Unrealized Gains 1 1
Unrealized Losses (202) (46)
Market Value 163,425 118,714
Level 2 | U.S. Treasury securities included in short-term investments    
Debt Securities, Available-for-sale [Line Items]    
Adjusted Cost   63,101
Unrealized Gains   4
Unrealized Losses   (1)
Market Value   63,104
Level 2 | U.S. government agency securities included in short-term investments    
Debt Securities, Available-for-sale [Line Items]    
Adjusted Cost 5,003 54,183
Unrealized Gains 0 10
Unrealized Losses 0 0
Market Value $ 5,003 $ 54,193