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FAIR VALUE MEASUREMENTS - SECURITIES WITH UNREALIZED LOSSES (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | $ 128,591 | $ 56,850
Less Than 12 Months - Gross Unrealized Losses | (170) | (33)
12 Months or Greater - Estimated Fair Value | 4,993 |
12 Months or Greater - Gross Unrealized Losses | (7) |
Total - Estimated Fair Value | 133,584 | 56,850
Total - Gross Unrealized Losses | (177) | (33)
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 | 15,567 |
Less Than 12 Months - Gross Unrealized Losses | (18) |
Total - Estimated Fair Value | 15,567 |
Total - Gross Unrealized Losses | (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 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 Greater - Estimated Fair Value | 4,993 |
12 Months or Greater - Gross Unrealized Losses | (7) |
Total - Estimated Fair Value | 6,493 |
Total - Gross Unrealized Losses | (7) |
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 |  | 4,999
Less Than 12 Months - Gross Unrealized Losses |  | (1)
Total - Estimated Fair Value |  | 4,999
Total - Gross Unrealized Losses |  | (1)
Commercial paper (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 66,872 | 22,956
Less Than 12 Months - Gross Unrealized Losses | (38) | (8)
Total - Estimated Fair Value | 66,872 | 22,956
Total - Gross Unrealized Losses | (38) | (8)
Corporate notes (due in less than one year) |  |
Schedule Of Available For Sale Securities [Line Items] |  |
Less Than 12 Months - Estimated Fair Value | 16,001 | 12,573
Less Than 12 Months - Gross Unrealized Losses | (17) | (7)
Total - Estimated Fair Value | 16,001 | 12,573
Total - Gross Unrealized Losses | (17) | (7)
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 | 16,322
Less Than 12 Months - Gross Unrealized Losses | (79) | (17)
Total - Estimated Fair Value | 24,145 | 16,322
Total - Gross Unrealized Losses | $ (79) | $ (17)

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