FAIR VALUE MEASUREMENTS (Tables)

12 Months Ended

Dec. 31, 2022

Fair Value Disclosures [Abstract]

Schedule of cash equivalents, restricted cash and marketable securities by security type

Cash equivalents, restricted cash and marketable securities by security type at December 31, 2022 were as follows:

			Gross		Gross
	Amortized		Unrealized		Unrealized			Estimated
(In thousands)	Cost		Gains		Losses			Fair Value
Included in cash and cash equivalents:
Money market funds	$	39,771	$	—	$	—		$	39,771
	$	39,771	$	—	$	—		$	39,771
Restricted cash:
Money market fund	$	93	$	—	$	—		$	93
Certificate of deposit		271		—		—			271
	$	364	$	—	$	—		$	364
Marketable securities:
U.S. Treasury securities (due in    less than one year)	$	12,983	$	—	$	(62	)	$	12,921
Municipal securities (due in less than one year)		3,000		—		(24	)		2,976
Government-sponsored enterprise securities    (due in less than one year)		9,860		—		(14	)		9,846
Commercial paper (due in less than one year)		64,285		6		(92	)		64,199
Corporate notes (due in less than one year)		26,014		—		(55	)		25,959
	$	116,142	$	6	$	(247	)	$	115,901

Cash equivalents, restricted cash and marketable securities by security type at December 31, 2021 were as follows:

			Gross		Gross
	Amortized		Unrealized		Unrealized			Estimated
(In thousands)	Cost		Gains		Losses			Fair Value
Included in cash and cash equivalents:
Money market funds	$	24,207	$	—	$	—		$	24,207
Commercial paper		7,499		—		—			7,499
	$	31,706	$	—	$	—		$	31,706
Restricted cash:
Money market fund	$	93	$	—	$	—		$	93
Certificate of deposit		271		—		—			271
	$	364	$	—	$	—		$	364
Marketable securities:
U.S. Treasury securities (due in    less than one year)	$	15,585	$	—	$	(18	)	$	15,567
U.S. Treasury securities (due in    one to two years)		1,524		—		(3	)		1,521
Municipal securities (due in    one to two years)		3,000		—		(15	)		2,985
Government-sponsored enterprise securities    (due in less than one year)		12,500		—		(7	)		12,493
Commercial paper (due in less than one year)		84,398		2		(38	)		84,362
Corporate notes (due in less than one year)		36,444		2		(17	)		36,429
Corporate notes (due in one to two years)		24,224		—		(79	)		24,145
	$	177,675	$	4	$	(177	)	$	177,502

Schedule of cash equivalents and marketable securities with unrealized losses

Cash equivalents and marketable securities with unrealized losses that have been in a continuous unrealized loss position for less than 12 months and 12 months or longer at December 31, 2022 and 2021 were as follows:

	Less Than 12 Months					12 Months or Greater					Total
			Gross					Gross					Gross
	Estimated		Unrealized			Estimated		Unrealized			Estimated		Unrealized
(In thousands)	Fair Value		Losses			Fair Value		Losses			Fair Value		Losses
As of December 31, 2022:
U.S. Treasury    securities (due in    less than one year)	$	11,424	$	(57	)	$	1,497	$	(5	)	$	12,921	$	(62	)
Municipal securities    (due in less than a    year)		—		—			2,976		(24	)		2,976		(24	)
Government-sponsored    enterprise securities    (due in less than    one year)		9,845		(14	)		—		—			9,845		(14	)
Commercial paper    (due in less than    one year)		52,454		(92	)		—		—			52,454		(92	)
Corporate notes (due in    less than one year)		1,998		(2	)		23,962		(53	)		25,960		(55	)
	$	75,721	$	(165	)	$	28,435	$	(82	)	$	104,156	$	(247	)
As of December 31, 2021:
U.S. Treasury    securities (due in    less than one year)	$	15,567	$	(18	)	$	—	$	—		$	15,567	$	(18	)
U.S. Treasury    securities (due in    one to two years)		1,521		(3	)		—		—			1,521		(3	)
Municipal securities    (due in one to two    years)		2,985		(15	)		—		—			2,985		(15	)
Government-sponsored    enterprise securities    (due in less than    one year)		1,500		—			4,993		(7	)		6,493		(7	)
Commercial paper    (due in less than    one year)		66,872		(38	)		—		—			66,872		(38	)
Corporate notes (due in    less than one year)		16,001		(17	)		—		—			16,001		(17	)
Corporate notes (due in    one to two years)		24,145		(79	)		—		—			24,145		(79	)
	$	128,591	$	(170	)	$	4,993	$	(7	)	$	133,584	$	(177	)

Schedule of financial instruments measured at fair value on recurring basis

The following table presents information about our financial instruments that are measured at fair value on a recurring basis as of December 31, 2022 and 2021 and indicates the fair value category assigned.

	Fair Value Measurements at Reporting Date Using
	Quoted Prices in				Significant
	Active Markets for		Significant Other		Unobservable
	Identical Assets		Observable Inputs		Inputs
(In thousands)	Level 1		Level 2		Level 3		Total
As of December 31, 2022:
Money market funds(1)(2)	$	39,864	$	—	$	—	$	39,864
Certificate of deposit(2)		271		—		—		271
U.S. Treasury securities(3)		—		12,921		—		12,921
Municipal securities(3)		—		2,976		—		2,976
Government-sponsored enterprise securities(3)		—		9,846		—		9,846
Commercial paper(3)		—		64,199		—		64,199
Corporate notes(3)		—		25,959		—		25,959
Total	$	40,135	$	115,901	$	—	$	156,036
As of December 31, 2021:
Money market funds(1)	$	24,207	$	—	$	—	$	24,207
U.S. Treasury securities(3)(4)		—		17,088		—		17,088
Municipal securities(4)		—		2,985		—		2,985
Government-sponsored enterprise securities(3)		—		12,493		—		12,493
Commercial paper(1)(3)		—		91,861		—		91,861
Corporate notes(3)(4)		—		60,574		—		60,574
Total	$	24,207	$	185,001	$	—	$	209,208

(1)Included in cash and cash equivalents on our consolidated balance sheets.

(2)Included in restricted cash on our consolidated balance sheets.

(3)Included in current portion of marketable securities on our consolidated balance sheets.

(4)Included in noncurrent portion of marketable securities on our consolidated balance sheets.