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Fair Value Measurements - Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Financial Assets: |  |
Cash and cash equivalents: | $ 492,022 | $ 225,130
Amortized Cost or Carrying Value | 1,773,331 | 1,954,699
Amortized Cost or Carrying Value | 4,220 | 3,220
Amortized Cost or Carrying Value | 1,777,551 | 1,957,919
Total financial assets | 2,269,573 | 2,183,049
Gross Unrealized Gains | 10,550 | 7,685
Gross Unrealized Losses Less Than 12 Months | (93) | (1,890)
Gross Unrealized Losses More Than 12 Months | (1) | (612)
Marketable securities, aggregate fair value | 1,783,787 | 1,959,882
Equity securities, aggregate fair value | 4,220 | 3,220
Investments, aggregate fair value | 1,788,007 | 1,963,102
Total financial assets | 2,280,029 | 2,188,232
Level 1 |  |
Financial Assets: |  |
Cash and cash equivalents: | 454,505 | 210,071
Marketable securities, aggregate fair value | 250,577 | 400,564
Equity securities, aggregate fair value | 4,220 | 3,220
Investments, aggregate fair value | 254,797 | 403,784
Total financial assets | 709,302 | 613,855
Level 2 |  |
Financial Assets: |  |
Cash and cash equivalents: | 37,517 | 15,059
Marketable securities, aggregate fair value | 1,533,210 | 1,559,318
Equity securities, aggregate fair value | 0 | 0
Investments, aggregate fair value | 1,533,210 | 1,559,318
Total financial assets | 1,570,727 | 1,574,377
Level 3 |  |
Financial Assets: |  |
Cash and cash equivalents: | 0 | 0
Marketable securities, aggregate fair value | 0 | 0
Equity securities, aggregate fair value | 0 | 0
Investments, aggregate fair value | 0 | 0
Total financial assets | 0 | 0
U.S. Treasury securities |  |
Financial Assets: |  |
Amortized Cost or Carrying Value | 249,396 | 379,846
Gross Unrealized Gains | 1,190 | 1,243
Gross Unrealized Losses Less Than 12 Months | (9) | (296)
Gross Unrealized Losses More Than 12 Months | 0 | (55)
Marketable securities, aggregate fair value | 250,577 | 380,738
U.S. Treasury securities | Level 1 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value | 250,577 | 380,738
U.S. Treasury securities | Level 2 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value | 0 | 0
U.S. Treasury securities | Level 3 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value | 0 | 0
Non-U.S. government securities |  |
Financial Assets: |  |
Amortized Cost or Carrying Value |  | 2,909
Gross Unrealized Gains |  | 27
Gross Unrealized Losses Less Than 12 Months |  | 0
Gross Unrealized Losses More Than 12 Months |  | 0
Marketable securities, aggregate fair value |  | 2,936
Non-U.S. government securities | Level 1 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value |  | 2,936
Non-U.S. government securities | Level 2 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value |  | 0
Non-U.S. government securities | Level 3 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value |  | 0
Corporate debt securities and commercial paper |  |
Financial Assets: |  |
Amortized Cost or Carrying Value | 1,523,935 | 1,571,944
Gross Unrealized Gains | 9,360 | 6,415
Gross Unrealized Losses Less Than 12 Months | (84) | (1,594)
Gross Unrealized Losses More Than 12 Months | (1) | (557)
Marketable securities, aggregate fair value | 1,533,210 | 1,576,208
Corporate debt securities and commercial paper | Level 1 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value | 0 | 16,890
Corporate debt securities and commercial paper | Level 2 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value | 1,533,210 | 1,559,318
Corporate debt securities and commercial paper | Level 3 |  |
Financial Assets: |  |
Marketable securities, aggregate fair value | 0 | 0
Money market funds |  |
Financial Assets: |  |
Cash and cash equivalents: | 454,505 | 207,323
Money market funds | Level 1 |  |
Financial Assets: |  |
Cash and cash equivalents: | 454,505 | 207,323
Money market funds | Level 2 |  |
Financial Assets: |  |
Cash and cash equivalents: | 0 | 0
Money market funds | Level 3 |  |
Financial Assets: |  |
Cash and cash equivalents: | 0 | 0
Commercial paper |  |
Financial Assets: |  |
Cash and cash equivalents: | 37,517 | 15,059
Commercial paper | Level 1 |  |
Financial Assets: |  |
Cash and cash equivalents: | 0 | 0
Commercial paper | Level 2 |  |
Financial Assets: |  |
Cash and cash equivalents: | 37,517 | 15,059
Commercial paper | Level 3 |  |
Financial Assets: |  |
Cash and cash equivalents: | $ 0 | 0
U.S. Treasury securities |  |
Financial Assets: |  |
Cash and cash equivalents: |  | 2,748
U.S. Treasury securities | Level 1 |  |
Financial Assets: |  |
Cash and cash equivalents: |  | 2,748
U.S. Treasury securities | Level 2 |  |
Financial Assets: |  |
Cash and cash equivalents: |  | 0
U.S. Treasury securities | Level 3 |  |
Financial Assets: |  |
Cash and cash equivalents: |  | $ 0

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