FAIR VALUE MEASUREMENTS - SECURITIES WITH UNREALIZED LOSSES (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
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)