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Fair Value Measurements (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024
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Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities |  | $ 1,983,725 |  | $ 2,056,008 |  |
1.75% Notes [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Interest rate on convertible senior notes |  | 1.75% |  | 1.75% |  | 1.75%
0% Notes [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Interest rate on convertible senior notes |  | 0.00% |  | 0.00% |  | 0.00%
Recurring Basis [Member] | Corporate Debt Securities [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities |  | $ 1,058,068 | [1] | $ 1,032,066 | [2] |
Recurring Basis [Member] | Corporate Debt Securities [Member] | Cash and Cash Equivalents [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities |  | 39,900 |  |  |  |
Recurring Basis [Member] | Debt Securities Issued by U.S. Government Agencies [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities | [2] | 150,590 |  | 208,998 |  |
Recurring Basis [Member] | Debt Securities Issued by U.S. Government Agencies [Member] | Cash and Cash Equivalents [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities |  | 6,000 |  |  |  |
Recurring Basis [Member] | Debt Securities Issued by the U.S. Treasury [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities |  | 768,085 | [3] | 806,724 | [2] |
Recurring Basis [Member] | Debt Securities Issued by the U.S. Treasury [Member] | Cash and Cash Equivalents [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities |  | 36,000 |  |  |  |
Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member] | 1.75% Notes [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Convertible notes |  | 794,500 |  | 569,300 |  |
Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member] | 0% Notes [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Convertible notes |  | 777,000 |  | 612,800 |  |
Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate Debt Securities [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities |  | 1,058,068 | [1] | 1,032,066 | [2] |
Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member] | Debt Securities Issued by U.S. Government Agencies [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities | [2] | 150,590 |  | 208,998 |  |
Recurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member] | Debt Securities Issued by the U.S. Treasury [Member] |  |  |  |  |  |
Fair Value Measurements [Abstract] |  |  |  |  |  |
Available-for-sale securities |  | $ 0 | [3] | $ 0 | [2] |
[1] | $39.9 million was included in cash and cash equivalents, with the difference included in short-term investments.
[2] | Included in short-term investments.
[3] | $36.0 million was included in cash and cash equivalents, with the difference included in short-term investments.

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