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Marketable Securities - Amortized Cost and Fair Value of Debt Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Fair Value to Amortized Cost |  |
Amortized Cost |  | $ 167,316
Allowance for Credit Losses |  | 0
Net Amortized Cost |  | 167,316
Gross Unrealized Gains |  | 34
Gross Unrealized Losses |  | (31)
Fair Value | $ 294,426 | 167,319
Cash and cash equivalents |  |
Fair Value to Amortized Cost |  |
Fair Value | 0 | 33,902
Marketable securities |  |
Fair Value to Amortized Cost |  |
Fair Value | 294,426 | 133,417
U.S. treasury bills |  |
Fair Value to Amortized Cost |  |
Amortized Cost | 294,211 | 113,908
Allowance for Credit Losses | 0 | 0
Net Amortized Cost | 294,211 | 113,908
Gross Unrealized Gains | 215 | 27
Gross Unrealized Losses | 0 | 0
Fair Value | $ 294,426 | 113,935
U.S. corporate bonds |  |
Fair Value to Amortized Cost |  |
Amortized Cost |  | 46,228
Allowance for Credit Losses |  | 0
Net Amortized Cost |  | 46,228
Gross Unrealized Gains |  | 7
Gross Unrealized Losses |  | (24)
Fair Value |  | 46,211
Foreign corporate bonds |  |
Fair Value to Amortized Cost |  |
Amortized Cost |  | 7,180
Allowance for Credit Losses |  | 0
Net Amortized Cost |  | 7,180
Gross Unrealized Gains |  | 0
Gross Unrealized Losses |  | (7)
Fair Value |  | $ 7,173

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