FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Included in cash and cash equivalents:
Amortized Cost	$ 39,771	$ 31,706
Estimated Fair Value	39,771	31,706
Restricted cash:
Amortized Cost	364	364
Estimated Fair Value	364	364
Marketable securities:
Amortized Cost	116,142	177,675
Gross Unrealized Gains	6	4
Gross Unrealized Losses	(247)	(177)
Estimated Fair Value	115,901	177,502
Money market funds
Included in cash and cash equivalents:
Amortized Cost	39,771	24,207
Estimated Fair Value	39,771	24,207
Restricted cash:
Amortized Cost	93	93
Estimated Fair Value	93	93
Commercial paper
Included in cash and cash equivalents:
Amortized Cost		7,499
Estimated Fair Value		7,499
Certificate of deposit
Restricted cash:
Amortized Cost	271	271
Estimated Fair Value	271	271
U.S. Treasury securities (due in less than one year)
Marketable securities:
Amortized Cost	12,983	15,585
Gross Unrealized Losses	(62)	(18)
Estimated Fair Value	12,921	15,567
U.S. Treasury securities (due in one to two years)
Marketable securities:
Amortized Cost		1,524
Gross Unrealized Losses		(3)
Estimated Fair Value		1,521
Municipal securities (due in less than one year)
Marketable securities:
Amortized Cost	3,000
Gross Unrealized Losses	(24)
Estimated Fair Value	2,976
Municipal securities (due in one to two years)
Marketable securities:
Amortized Cost		3,000
Gross Unrealized Losses		(15)
Estimated Fair Value		2,985
Government-sponsored enterprise securities (due in less than one year)
Marketable securities:
Amortized Cost	9,860	12,500
Gross Unrealized Losses	(14)	(7)
Estimated Fair Value	9,846	12,493
Commercial paper (due in less than one year)
Marketable securities:
Amortized Cost	64,285	84,398
Gross Unrealized Gains	6	2
Gross Unrealized Losses	(92)	(38)
Estimated Fair Value	64,199	84,362
Corporate notes (due in less than one year)
Marketable securities:
Amortized Cost	26,014	36,444
Gross Unrealized Gains		2
Gross Unrealized Losses	(55)	(17)
Estimated Fair Value	$ 25,959	36,429
Corporate notes (due in one to two years)
Marketable securities:
Amortized Cost		24,224
Gross Unrealized Losses		(79)
Estimated Fair Value		$ 24,145

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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