FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Included in cash and cash equivalents:
Amortized Cost	$ 51,521	$ 31,706
Gross Unrealized Losses	(7)
Estimated Fair Value	51,514	31,706
Restricted cash:
Amortized Cost	364	364
Estimated Fair Value	364	364
Marketable securities:
Amortized Cost	134,318	177,675
Gross Unrealized Gains	3	4
Gross Unrealized Losses	(637)	(177)
Estimated Fair Value	133,684	177,502
Money market funds
Included in cash and cash equivalents:
Amortized Cost	17,362	24,207
Estimated Fair Value	17,362	24,207
Restricted cash:
Amortized Cost	93	93
Estimated Fair Value	93	93
Commercial paper
Included in cash and cash equivalents:
Amortized Cost	34,159	7,499
Gross Unrealized Losses	(7)
Estimated Fair Value	34,152	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	24,493	15,585
Gross Unrealized Losses	(174)	(18)
Estimated Fair Value	24,319	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	(50)
Estimated Fair Value	2,950
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	13,325	12,500
Gross Unrealized Gains	3
Gross Unrealized Losses	(29)	(7)
Estimated Fair Value	13,299	12,493
Commercial paper (due in less than one year)
Marketable securities:
Amortized Cost	67,432	84,398
Gross Unrealized Gains		2
Gross Unrealized Losses	(215)	(38)
Estimated Fair Value	67,217	84,362
Corporate notes (due in less than one year)
Marketable securities:
Amortized Cost	26,068	36,444
Gross Unrealized Gains		2
Gross Unrealized Losses	(169)	(17)
Estimated Fair Value	$ 25,899	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

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