Marketable Securities

6 Months Ended

Jun. 30, 2024

Investments, Debt and Equity Securities [Abstract]

4. Marketable Securities

The Company has classified its marketable securities as available-for-sale securities. These securities are carried at estimated fair value with unrealized holding gains and losses included in accumulated other comprehensive loss in stockholders’ equity until realized. Gains and losses on marketable security transactions are reported on the specific-identification method. Dividend and interest income are recognized when earned.

The amortized cost, gross unrealized holding gains, gross unrealized holding losses, and fair value for available-for-sale securities by major security type and class of securities as of June 30, 2024 and December 31, 2023 were as follows:

	Amortized cost		Gross unrealized holding gains		Gross unrealized holding losses			Estimated fair value
June 30, 2024
Available-for-sale securities:
US Treasury securities	$	505	$	—	$	—		$	505
Mutual funds		1,545		6		(1	)		1,550
Certificates of deposit		418		—		—			418
Corporate debt securities	$	—	$	—	$	—		$	—
Total available-for-sale securities	$	2,468	$	6	$	(1	)	$	2,473

	Amortized cost		Gross unrealized holding gains		Gross unrealized holding losses			Estimated fair value
December 31, 2023
Available-for-sale securities:
US Treasury securities	$	1,804	$	—	$	(1	)	$	1,803
Mutual funds		1,498		7		—			1,505
Certificates of deposit		103		—		—			103
Corporate debt securities	$	1,007	$	—	$	(22	)	$	985
Total available-for-sale securities	$	4,412	$	7	$	(23	)	$	4,396

	Amortized cost		Estimated fair value
Due within one year	$	1,847	$	1,852
Due after one year through five years		622		621
Due after five years		—		—
Total available-for-sale securities	$	2,469	$	2,473

Debt securities in an unrealized loss position as of June 30, 2024 were not deemed impaired at acquisition and subsequent declines in fair value are not deemed attributed to declines in credit quality. Management believes that it is more likely than not that the securities will receive a full recovery of par value, although there can be no assurance that such recovery will occur. The available-for-sale marketable securities with continuous gross unrealized loss position for less than 12 months and 12 months or greater and their related fair values were as follows:

	Less than 12 months					More than 12 months				Total
	Estimated fair value		Gross unrealized holding losses			Estimated fair value		Gross unrealized holding losses		Estimated fair value		Gross unrealized holding losses
As of June 30, 2024
US Treasury securities	$	505	$	—		$	—	$	—	$	505	$	—
Mutual Funds		1,550		(1	)		—		—		1,550		(1	)
Certificates of Deposit		418		—			—		—		418		—
Corporate debt securities		—		—			—		—		—		—
Total	$	2,473	$	(1	)	$	—	$	—	$	2,473	$	(1	)

	Less than 12 months					More than 12 months				Total
	Estimated fair value		Gross unrealized holding losses			Estimated fair value		Gross unrealized holding losses		Estimated fair value		Gross unrealized holding losses
As of December 31, 2023
US Treasury securities	$	1,803	$	(1	)	$	—	$	—	$	1,803	$	(1	)
Mutual Funds		1,505		—			—		—		1,505		—
Certificates of Deposit		103		—			—		—		103		—
Corporate debt securities		985		(22	)		—		—		985		(22	)
Total	$	4,396	$	(23	)	$	—	$	—	$	4,396	$	(23	)