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Investments and Fair Value Measurements - Available-For-Sale Investments (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 287,307 | $ 548,333
Gross Unrealized Gain | 23 | 0
Gross Unrealized Loss | (957) | (8,647)
Fair Value | 286,373 | 539,686
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 73,444 | 291,685
Gross Unrealized Gain | 8 | 0
Gross Unrealized Loss | (4) | (3,697)
Fair Value | 73,448 | 287,988
Corporate notes and bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 112,487 | 217,187
Gross Unrealized Gain | 9 | 0
Gross Unrealized Loss | (931) | (4,494)
Fair Value | 111,565 | 212,693
Commercial paper |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 25,946 |
Gross Unrealized Gain | 0 |
Gross Unrealized Loss | (12) |
Fair Value | 25,934 |
Asset-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 89 | 24,617
Gross Unrealized Gain | 0 | 0
Gross Unrealized Loss | 0 | (286)
Fair Value | 89 | 24,331
Municipal securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost |  | 2,322
Gross Unrealized Gain |  | 0
Gross Unrealized Loss |  | (101)
Fair Value |  | 2,221
Foreign government and supranational securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost |  | 12,522
Gross Unrealized Gain |  | 0
Gross Unrealized Loss |  | (69)
Fair Value |  | $ 12,453
Agency bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 9,854 |
Gross Unrealized Gain | 0 |
Gross Unrealized Loss | (3) |
Fair Value | 9,851 |
U.S. Treasury securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 52,824 |
Gross Unrealized Gain | 6 |
Gross Unrealized Loss | 0 |
Fair Value | 52,830 |
Commercial paper |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 12,663 |
Gross Unrealized Gain | 0 |
Gross Unrealized Loss | (7) |
Fair Value | $ 12,656 |

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