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Investments - Summary of Investments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Total
Amortized Cost	$ 8,481	$ 11,735
Gross Unrealized Gains	1,015	246
Gross Unrealized Losses	0	(80)
Estimated Fair Value	9,496	11,901
Mutual funds
Equity securities
Amortized Cost	7,002	6,352
Gross Unrealized Gains	711	0
Gross Unrealized Losses	0	(11)
Estimated Fair Value	7,713	6,341
U.S. Government and agency securities
Available-for-sale securities
Amortized Cost		3,247
Gross Unrealized Gains		10
Gross Unrealized Losses		(4)
Estimated Fair Value		3,253
Corporate bonds
Available-for-sale securities
Amortized Cost	1,479	2,033
Gross Unrealized Gains	304	236
Gross Unrealized Losses	0	(4)
Estimated Fair Value	$ 1,783	2,265
Asset-backed securities and collateralized mortgage obligations
Available-for-sale securities
Amortized Cost		103
Gross Unrealized Gains		0
Gross Unrealized Losses		(61)
Estimated Fair Value		$ 42

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