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Fair Value Measurements - Fair Value of Financial Assets Measured on Recurring Basis (Details) - Fair Value Measurements Recurring - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Assets: |  |
Total | $ 353,029 | $ 330,430
Level 1 |  |
Assets: |  |
Total | 192,437 | 159,757
Level 2 |  |
Assets: |  |
Total | 160,592 | 170,673
Money Market Funds |  |
Assets: |  |
Total | 54,078 | 36,486
Money Market Funds | Level 1 |  |
Assets: |  |
Total | 54,078 | 36,486
Commercial Paper |  |
Assets: |  |
Total | 78,348 | 87,140
Commercial Paper | Level 2 |  |
Assets: |  |
Total | 78,348 | 87,140
Corporate Debt Securities |  |
Assets: |  |
Total | 54,494 | 36,429
Corporate Debt Securities | Level 2 |  |
Assets: |  |
Total | 54,494 | 36,429
Equity Securities |  |
Assets: |  |
Total | 34,043 | 32,020
Equity Securities | Level 1 |  |
Assets: |  |
Total | 34,043 | 32,020
Asset-backed Securities |  |
Assets: |  |
Total | 27,750 | 14,016
Asset-backed Securities | Level 2 |  |
Assets: |  |
Total | 27,750 | 14,016
U.S. Government Securities |  |
Assets: |  |
Total | 104,316 | 91,251
U.S. Government Securities | Level 1 |  |
Assets: |  |
Total | $ 104,316 | 91,251
U.S. Agency Securities |  |
Assets: |  |
Total |  | 16,607
U.S. Agency Securities | Level 2 |  |
Assets: |  |
Total |  | 16,607
Supranational Debt Securities |  |
Assets: |  |
Total |  | 16,481
Supranational Debt Securities | Level 2 |  |
Assets: |  |
Total |  | $ 16,481

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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