Investment Securities - Summary of Investment Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	$ 350,269	$ 412,570
Unrealized Gains	11	490
Unrealized (Losses)	(679)	(386)
Estimated Fair Value	349,601	412,674
U.S. Government Agency Securities
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	91,148	150,651
Unrealized Gains	5	148
Unrealized (Losses)	(142)	(204)
Estimated Fair Value	91,011	150,595
FDIC Certificates of Deposit
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	1,470	4,410
Unrealized Gains	0	2
Unrealized (Losses)	(1)	(12)
Estimated Fair Value	1,469	4,400
Certificates of Deposit
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	60,000	60,000
Unrealized Gains	0	0
Unrealized (Losses)	0	0
Estimated Fair Value	60,000	60,000
Commercial Paper
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	33,669	78,610
Unrealized Gains	0	59
Unrealized (Losses)	(19)	(27)
Estimated Fair Value	33,650	78,642
Corporate Notes/Bonds
Debt Securities, Available-for-Sale [Line Items]
Amortized Cost	163,982	118,899
Unrealized Gains	6	281
Unrealized (Losses)	(517)	(143)
Estimated Fair Value	$ 163,471	$ 119,037

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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