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FAIR VALUE MEASUREMENTS - SECURITIES WITH UNREALIZED LOSSES (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | $ 152,345 | $ 128,591
Less Than 12 Months - Gross Unrealized Losses | (580) | (170)
12 Months or Longer - Estimated Fair Value | 18,390 | 4,993
12 Months or Longer - Gross Unrealized Losses | (221) | (7)
Total - Estimated Fair Value | 170,735 | 133,584
Total - Gross Unrealized Losses | (801) | (177)
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 | 30,812 | 15,567
Less Than 12 Months - Gross Unrealized Losses | (207) | (18)
Total - Estimated Fair Value | 30,812 | 15,567
Total - Gross Unrealized Losses | (207) | (18)
U.S. Treasury securities (due in one to two years) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value |  | 1,521
Less Than 12 Months - Gross Unrealized Losses |  | (3)
Total - Estimated Fair Value |  | 1,521
Total - Gross Unrealized Losses |  | (3)
Municipal securities (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 2,943 |
Less Than 12 Months - Gross Unrealized Losses | (57) |
Total - Estimated Fair Value | 2,943 |
Total - Gross Unrealized Losses | (57) |
Municipal securities (due in one to two years) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value |  | 2,985
Less Than 12 Months - Gross Unrealized Losses |  | (15)
Total - Estimated Fair Value |  | 2,985
Total - Gross Unrealized Losses |  | (15)
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 |  | 1,500
12 Months or Longer - Estimated Fair Value | 4,953 | 4,993
12 Months or Longer - Gross Unrealized Losses | (47) | (7)
Total - Estimated Fair Value | 4,953 | 6,493
Total - Gross Unrealized Losses | (47) | (7)
Commercial paper (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 94,341 | 66,872
Less Than 12 Months - Gross Unrealized Losses | (214) | (38)
Total - Estimated Fair Value | 94,341 | 66,872
Total - Gross Unrealized Losses | (214) | (38)
Corporate notes (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 24,249 | 16,001
Less Than 12 Months - Gross Unrealized Losses | (102) | (17)
12 Months or Longer - Estimated Fair Value | 13,437 |
12 Months or Longer - Gross Unrealized Losses | (174) |
Total - Estimated Fair Value | 37,686 | 16,001
Total - Gross Unrealized Losses | $ (276) | (17)
Corporate notes (due in one to two years) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value |  | 24,145
Less Than 12 Months - Gross Unrealized Losses |  | (79)
Total - Estimated Fair Value |  | 24,145
Total - Gross Unrealized Losses |  | $ (79)

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