FAIR VALUE MEASUREMENTS - SECURITIES WITH UNREALIZED LOSSES (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
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)