Marketable Securities - Schedule of Available-For-Sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Available-for-sale securities:
Amortized Cost	$ 13,284	$ 13,257
Gross Unrealized Gain	1	2
Gross Unrealized (Losses)	(141)	(223)
Estimated Fair Value	13,144	13,036
Tax-exempt municipal securities
Available-for-sale securities:
Amortized Cost	10,083	10,055
Gross Unrealized Gain	1	2
Gross Unrealized (Losses)	(87)	(144)
Estimated Fair Value	9,997	9,913
Corporate debt securities
Available-for-sale securities:
Amortized Cost	3,201	3,202
Gross Unrealized Gain	0	0
Gross Unrealized (Losses)	(54)	(79)
Estimated Fair Value	3,147	3,123
Term deposits
Held-to-maturity securities:
Amortized Cost	18,304	27,175
Gross Unrealized Gain	0	0
Gross Unrealized (Losses)	0	0
Estimated Fair Value	$ 18,304	$ 27,175

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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