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FAIR VALUE MEASUREMENTS - SECURITIES WITH UNREALIZED LOSSES (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
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Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | $ 351,581 | $ 75,721
Less Than 12 Months - Gross Unrealized Losses | (972) | (165)
12 Months or Longer - Estimated Fair Value |  | 28,435
12 Months or Longer - Gross Unrealized Losses |  | (82)
Total - Estimated Fair Value | 351,581 | 104,156
Total - Gross Unrealized Losses | (972) | (247)
U.S. Treasury securities (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 26,446 | 11,424
Less Than 12 Months - Gross Unrealized Losses | (22) | (57)
12 Months or Longer - Estimated Fair Value |  | 1,497
12 Months or Longer - Gross Unrealized Losses |  | (5)
Total - Estimated Fair Value | 26,446 | 12,921
Total - Gross Unrealized Losses | (22) | (62)
Municipal securities (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
12 Months or Longer - Estimated Fair Value |  | 2,976
12 Months or Longer - Gross Unrealized Losses |  | (24)
Total - Estimated Fair Value |  | 2,976
Total - Gross Unrealized Losses |  | (24)
Government-sponsored enterprise securities (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 94,523 | 9,845
Less Than 12 Months - Gross Unrealized Losses | (293) | (14)
Total - Estimated Fair Value | 94,523 | 9,845
Total - Gross Unrealized Losses | (293) | (14)
Government-sponsored enterprise securities (due in one to two years) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 10,651 |
Less Than 12 Months - Gross Unrealized Losses | (35) |
Total - Estimated Fair Value | 10,651 |
Total - Gross Unrealized Losses | (35) |
Commercial paper (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 149,584 | 52,454
Less Than 12 Months - Gross Unrealized Losses | (281) | (92)
Total - Estimated Fair Value | 149,584 | 52,454
Total - Gross Unrealized Losses | (281) | (92)
Corporate notes (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 39,438 | 1,998
Less Than 12 Months - Gross Unrealized Losses | (160) | (2)
12 Months or Longer - Estimated Fair Value |  | 23,962
12 Months or Longer - Gross Unrealized Losses |  | (53)
Total - Estimated Fair Value | 39,438 | 25,960
Total - Gross Unrealized Losses | (160) | $ (55)
Corporate notes (due in one to two years) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 30,939 |
Less Than 12 Months - Gross Unrealized Losses | (181) |
Total - Estimated Fair Value | 30,939 |
Total - Gross Unrealized Losses | $ (181) |

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