Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 120,498	$ 140,377
Available-for-sale marketable securities, Unrealized Gain	58	249
Available-for-sale marketable securities, Unrealized (Loss)	(9,888)	(8,170)
Available-for-sale marketable securities, Fair Market Value	110,668	132,456
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	78,320	87,538
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	45,305	45,725
Available-for-sale marketable securities, Unrealized Gain	0	14
Available-for-sale marketable securities, Unrealized (Loss)	(4,742)	(3,931)
Available-for-sale marketable securities, Fair Market Value	40,563	41,808
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	40,563	35,080
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	39,750	56,458
Available-for-sale marketable securities, Unrealized Gain	58	201
Available-for-sale marketable securities, Unrealized (Loss)	(4,767)	(3,925)
Available-for-sale marketable securities, Fair Market Value	35,041	52,734
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	30,671	44,263
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	0	1,633
Available-for-sale marketable securities, Unrealized Gain	0	34
Available-for-sale marketable securities, Unrealized (Loss)		0
Available-for-sale marketable securities, Fair Market Value	0	1,667
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		0
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	3,928	4,898
Available-for-sale marketable securities, Unrealized Gain		0
Available-for-sale marketable securities, Unrealized (Loss)	(23)	(6)
Available-for-sale marketable securities, Fair Market Value	3,905	4,892
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	3,905	4,892
Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	9,060	9,081
Available-for-sale marketable securities, Unrealized Gain		0
Available-for-sale marketable securities, Unrealized (Loss)	(356)	(308)
Available-for-sale marketable securities, Fair Market Value	8,704	8,773
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	3,181	3,303
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	21,688	21,772
Available-for-sale marketable securities, Unrealized Gain		0
Available-for-sale marketable securities, Unrealized (Loss)		0
Available-for-sale marketable securities, Fair Market Value	21,688	21,772
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		0
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	767	810
Available-for-sale marketable securities, Unrealized Gain		0
Available-for-sale marketable securities, Unrealized (Loss)		0
Available-for-sale marketable securities, Fair Market Value	767	810
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		$ 0

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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