Summary of Available-for-Sale Securities (Detail) - USD ($)	Jun. 30, 2024	Dec. 31, 2023	Jun. 30, 2023
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 61,204,000	$ 60,456,000
Gross Unrealized Gain	12,000	26,000
Gross Unrealized Loss	(783,000)	(1,215,000)
Allowance for Credit Loss	0	0	$ 0
Fair Value	60,433,000	59,267,000
Money market funds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,641,000	5,062,000
Gross Unrealized Gain
Gross Unrealized Loss	0
Allowance for Credit Loss	0	0
Fair Value	1,641,000	5,062,000
United States government agency securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	23,668,000	19,652,000
Gross Unrealized Gain	12,000	16,000
Gross Unrealized Loss	(210,000)	(314,000)
Allowance for Credit Loss	0	0
Fair Value	23,470,000	19,354,000
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	32,668,000	32,395,000
Gross Unrealized Gain		3,000
Gross Unrealized Loss	(232,000)	(638,000)
Allowance for Credit Loss	0	0
Fair Value	32,436,000	31,760,000
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,227,000	3,347,000
Gross Unrealized Gain		7,000
Gross Unrealized Loss	(341,000)	(263,000)
Allowance for Credit Loss	0	0
Fair Value	$ 2,886,000	$ 3,091,000