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Fair Value Measurements - Assets Measured at Fair Value On a Recurring Basis (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Available-for-Sale | $ 750,461 | $ 707,109
Cash equivalents |  |
Cash Equivalents | 84,679 | 160,150
Short-term |  |
Debt Securities, Available-for-Sale | 632,959 | 495,234
Long-term |  |
Debt Securities, Available-for-Sale | 32,823 | 51,725
Level 1 |  |
Debt Securities, Available-for-Sale | 42,833 | 41,494
Level 1 | Cash equivalents |  |
Cash Equivalents | 42,833 | 41,494
Level 1 | Short-term |  |
Debt Securities, Available-for-Sale | 0 | 0
Level 1 | Long-term |  |
Debt Securities, Available-for-Sale | 0 | 0
Level 2 |  |
Debt Securities, Available-for-Sale | 707,628 | 665,615
Level 2 | Cash equivalents |  |
Cash Equivalents | 41,846 | 118,656
Level 2 | Short-term |  |
Debt Securities, Available-for-Sale | 632,959 | 495,234
Level 2 | Long-term |  |
Debt Securities, Available-for-Sale | 32,823 | 51,725
US Government and agency obligations | Cash equivalents |  |
Cash Equivalents | 16,901 | 81,535
US Government and agency obligations | Short-term |  |
Debt Securities, Available-for-Sale | 67,696 | 94,295
US Government and agency obligations | Long-term |  |
Debt Securities, Available-for-Sale | 2,696 | 10,452
US Government and agency obligations | Level 1 | Cash equivalents |  |
Cash Equivalents | 0 | 0
US Government and agency obligations | Level 1 | Short-term |  |
Debt Securities, Available-for-Sale | 0 | 0
US Government and agency obligations | Level 1 | Long-term |  |
Debt Securities, Available-for-Sale | 0 | 0
US Government and agency obligations | Level 2 | Cash equivalents |  |
Cash Equivalents | 16,901 | 81,535
US Government and agency obligations | Level 2 | Short-term |  |
Debt Securities, Available-for-Sale | 67,696 | 94,295
US Government and agency obligations | Level 2 | Long-term |  |
Debt Securities, Available-for-Sale | 2,696 | 10,452
Money market funds | Cash equivalents |  |
Cash Equivalents | 42,833 | 41,494
Money market funds | Level 1 | Cash equivalents |  |
Cash Equivalents | 42,833 | 41,494
Money market funds | Level 2 | Cash equivalents |  |
Cash Equivalents | 0 | 0
Commercial paper | Cash equivalents |  |
Cash Equivalents | 14,712 | 22,689
Commercial paper | Short-term |  |
Debt Securities, Available-for-Sale | 179,697 | 149,807
Commercial paper | Level 1 | Cash equivalents |  |
Cash Equivalents | 0 | 0
Commercial paper | Level 1 | Short-term |  |
Debt Securities, Available-for-Sale | 0 | 0
Commercial paper | Level 2 | Cash equivalents |  |
Cash Equivalents | 14,712 | 22,689
Commercial paper | Level 2 | Short-term |  |
Debt Securities, Available-for-Sale | 179,697 | 149,807
Certificates of deposit | Short-term |  |
Debt Securities, Available-for-Sale | 27,960 | 7,239
Certificates of deposit | Level 1 | Short-term |  |
Debt Securities, Available-for-Sale | 0 | 0
Certificates of deposit | Level 2 | Short-term |  |
Debt Securities, Available-for-Sale | 27,960 | 7,239
Corporate debt securities | Cash equivalents |  |
Cash Equivalents | 5,713 | 4,133
Corporate debt securities | Short-term |  |
Debt Securities, Available-for-Sale | 337,988 | 242,313
Corporate debt securities | Long-term |  |
Debt Securities, Available-for-Sale | 30,127 | 39,931
Corporate debt securities | Level 1 | Cash equivalents |  |
Cash Equivalents | 0 | 0
Corporate debt securities | Level 1 | Short-term |  |
Debt Securities, Available-for-Sale | 0 | 0
Corporate debt securities | Level 1 | Long-term |  |
Debt Securities, Available-for-Sale | 0 | 0
Corporate debt securities | Level 2 | Cash equivalents |  |
Cash Equivalents | 5,713 | 4,133
Corporate debt securities | Level 2 | Short-term |  |
Debt Securities, Available-for-Sale | 337,988 | 242,313
Corporate debt securities | Level 2 | Long-term |  |
Debt Securities, Available-for-Sale | 30,127 | 39,931
Municipal debt securities | Cash equivalents |  |
Cash Equivalents | 4,520 | 10,299
Municipal debt securities | Short-term |  |
Debt Securities, Available-for-Sale | 19,618 | 1,580
Municipal debt securities | Long-term |  |
Debt Securities, Available-for-Sale | 0 | 1,342
Municipal debt securities | Level 1 | Cash equivalents |  |
Cash Equivalents | 0 | 0
Municipal debt securities | Level 1 | Short-term |  |
Debt Securities, Available-for-Sale | 0 | 0
Municipal debt securities | Level 1 | Long-term |  |
Debt Securities, Available-for-Sale | 0 | 0
Municipal debt securities | Level 2 | Cash equivalents |  |
Cash Equivalents | 4,520 | 10,299
Municipal debt securities | Level 2 | Short-term |  |
Debt Securities, Available-for-Sale | 19,618 | 1,580
Municipal debt securities | Level 2 | Long-term |  |
Debt Securities, Available-for-Sale | $ 0 | $ 1,342

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