Note 5 - Marketable Securities

12 Months Ended

Dec. 31, 2023

Notes to Financial Statements

Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]

5. Marketable Securities

The objectives of the Company’s investment policy are to ensure the safety and preservation of invested funds, as well as to maintain liquidity sufficient to meet cash flow requirements. The Company invests its excess cash in securities issued by financial institutions, commercial companies, and government agencies that management believes to be of high credit quality in order to limit the amount of its credit exposure. The Company has not realized any net losses from its investments.

Unrealized gains and losses on investments that are available for sale are recognized in accumulated comprehensive loss, unless an unrealized loss is considered to be other than temporary, in which case the unrealized loss is charged to operations. The Company periodically reviews its investments for other than temporary declines in fair value below cost basis and whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable.

The Company believes the individual unrealized losses represent temporary declines primarily resulting from interest rate changes. Realized gains and losses are included in other income in the consolidated statements of operations and comprehensive loss and are determined using the specific identification method with transactions recorded on a trade date basis. The Company classifies marketable securities that are available for use in current operations as current assets on the consolidated balance sheet.

The following tables summarize marketable securities held at December 31, 2023 and 2022 (in thousands):

	Fair Value Measurements as of December 31, 2023 Using:
	Amortized Cost		Unrealized gains		Unrealized Losses			Fair Value
Assets
Corporate bonds	$	54,256	$	74	$	(49	)	$	54,281
Commercial paper		28,507		30		(3	)		28,534
Certificates of deposit		18,850		17		(1	)		18,866
U.S. government treasuries		16,127		3		(50	)		16,080
Asset-backed securities		10,456		23		(7	)		10,472
Total assets	$	128,196	$	147	$	(110	)	$	128,233

	Fair Value Measurements as of December 31, 2022 Using:
	Amortized Cost		Unrealized gains		Unrealized Losses			Fair Value
Assets
Corporate bonds	$	87,998	$	12	$	(250	)	$	87,760
Commercial paper		37,680		33		(31	)		37,682
Certificates of deposit		19,689		16		(38	)		19,667
Asset-backed securities		6,598		3		(47	)		6,554
Total assets	$	151,965	$	64	$	(366	)	$	151,663

	As of December 31,
	2023		2022
Maturing in one year or less		93,117		134,620
Maturing after one year through two years		35,116		17,043
Total	$	128,233	$	151,663