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Fair Value of Financial Assets and Liabilities - By Type of Security (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Marketable securities: |  |
Book Value | $ 125,357 | $ 142,108
Gross Unrealized Gain | 509 | 160
Gross Unrealized Loss | (81) | (269)
Fair Value | 125,785 | 141,999
Corporate debt securities |  |
Marketable securities: |  |
Book Value | 73,258 | 52,362
Gross Unrealized Gain | 414 | 65
Gross Unrealized Loss | (36) | (142)
Fair Value | 73,636 | 52,285
Debt securities, maturity dates between one and five years | $ 40,500 | $ 28,000
Corporate debt securities | Minimum |  |
Marketable securities: |  |
Marketable securities maturity period | 1 year | 1 year
Corporate debt securities | Maximum |  |
Marketable securities: |  |
Marketable securities maturity period | 2 years | 2 years
Commercial paper |  |
Marketable securities: |  |
Book Value |  | $ 12,345
Gross Unrealized Gain |  | 2
Gross Unrealized Loss |  | (1)
Fair Value |  | 12,346
Asset-backed debt securities |  |
Marketable securities: |  |
Book Value | $ 4,981 | 10,953
Gross Unrealized Gain |  | 42
Gross Unrealized Loss | (3) | (30)
Fair Value | 4,978 | 10,965
Debt securities, maturity dates between one and five years |  | $ 6,200
Asset-backed debt securities | Minimum |  |
Marketable securities: |  |
Marketable securities maturity period |  | 1 year
Asset-backed debt securities | Maximum |  |
Marketable securities: |  |
Marketable securities maturity period |  | 3 years
Foreign government agency debt securities |  |
Marketable securities: |  |
Book Value | 4,872 | $ 4,698
Gross Unrealized Gain | 32 | 43
Fair Value | 4,904 | 4,741
Debt securities, maturity dates between one and five years |  | $ 4,700
Foreign government agency debt securities | Minimum |  |
Marketable securities: |  |
Marketable securities maturity period |  | 1 year
Foreign government agency debt securities | Maximum |  |
Marketable securities: |  |
Marketable securities maturity period |  | 2 years
U.S. government and government agency debt securities |  |
Marketable securities: |  |
Book Value | 42,246 | $ 61,750
Gross Unrealized Gain | 63 | 8
Gross Unrealized Loss | (42) | (96)
Fair Value | 42,267 | 61,662
Debt securities, maturity dates between one and five years | $ 5,100 | $ 23,900
U.S. government and government agency debt securities | Minimum |  |
Marketable securities: |  |
Marketable securities maturity period | 1 year | 1 year
U.S. government and government agency debt securities | Maximum |  |
Marketable securities: |  |
Marketable securities maturity period | 2 years | 2 years

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