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Fair Value Measurements and Available for Sale Investments - Available-for-sale Investments (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 382,555 | $ 517,907
Gross Unrealized Gains | 199 | 38
Gross Unrealized Losses | (789) | (5,077)
Total Fair Value | 381,965 | 512,868
Short-term investments | 354,939 | 369,933
Long-term investments | 27,026 | 142,935
Agency securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 20,322 | 75,504
Gross Unrealized Gains | 0 | 11
Gross Unrealized Losses | (69) | (913)
Total Fair Value | 20,253 | 74,602
Short-term investments | 20,300 | 57,100
Long-term investments | $ 0 | $ 17,500
Agency securities | Minimum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Remaining maturity (in years) | 1 year | 1 year
Agency securities | Maximum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Remaining maturity (in years) | 2 years | 2 years
Certificates of deposit |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 246 | $ 2,915
Gross Unrealized Gains | 0 | 0
Gross Unrealized Losses | (2) | (59)
Total Fair Value | 244 | 2,856
Short-term investments | 200 | 2,600
Long-term investments | $ 0 | $ 300
Certificates of deposit | Minimum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Remaining maturity (in years) | 1 year | 1 year
Certificates of deposit | Maximum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Remaining maturity (in years) | 2 years | 2 years
Commercial and corporate obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 35,760 | $ 61,791
Gross Unrealized Gains | 77 | 8
Gross Unrealized Losses | (83) | (916)
Total Fair Value | 35,754 | 60,883
Short-term investments | 25,800 | 44,000
Long-term investments | $ 10,000 | $ 16,900
Commercial and corporate obligations | Minimum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Remaining maturity (in years) | 1 year | 1 year
Commercial and corporate obligations | Maximum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Remaining maturity (in years) | 2 years | 2 years
US Treasury Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 326,227 | $ 377,697
Gross Unrealized Gains | 122 | 19
Gross Unrealized Losses | (635) | (3,189)
Total Fair Value | 325,714 | 374,527
Short-term investments | 308,600 | 266,200
Long-term investments | $ 17,100 | $ 108,300
US Treasury Securities | Minimum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Remaining maturity (in years) | 1 year | 1 year
US Treasury Securities | Maximum |  |
Debt Securities, Available-for-sale [Line Items] |  |
Remaining maturity (in years) | 2 years | 2 years

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