FAIR VALUE MEASUREMENTS - SECURITY TYPE (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Included in cash and cash equivalents:
Amortized Cost	$ 69,032	$ 31,706
Gross Unrealized Losses	(10)
Estimated Fair Value	69,022	31,706
Restricted cash:
Amortized Cost	364	364
Estimated Fair Value	364	364
Marketable securities:
Amortized Cost	144,014	177,675
Gross Unrealized Gains	7	4
Gross Unrealized Losses	(791)	(177)
Estimated Fair Value	143,230	177,502
Money market funds
Included in cash and cash equivalents:
Amortized Cost	24,789	24,207
Estimated Fair Value	24,789	24,207
Restricted cash:
Amortized Cost	93	93
Estimated Fair Value	93	93
Commercial paper
Included in cash and cash equivalents:
Amortized Cost	44,243	7,499
Gross Unrealized Losses	(10)
Estimated Fair Value	44,233	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	31,019	15,585
Gross Unrealized Losses	(207)	(18)
Estimated Fair Value	30,812	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	(57)
Estimated Fair Value	2,943
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	5,000	12,500
Gross Unrealized Losses	(47)	(7)
Estimated Fair Value	4,953	12,493
Commercial paper (due in less than one year)
Marketable securities:
Amortized Cost	67,034	84,398
Gross Unrealized Gains	7	2
Gross Unrealized Losses	(204)	(38)
Estimated Fair Value	66,837	84,362
Corporate notes (due in less than one year)
Marketable securities:
Amortized Cost	37,961	36,444
Gross Unrealized Gains		2
Gross Unrealized Losses	(276)	(17)
Estimated Fair Value	$ 37,685	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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