Note 5 - Investments, Available-for-sale

12 Months Ended

Dec. 31, 2022

Notes to Financial Statements

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

5. Investments, available-for-sale

The aggregate fair values of investment securities along with cumulative unrealized gains and losses determined on an individual investment security basis and included in other comprehensive loss are as follows:

	December 31, 2022
	(in thousands)
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Short-term investments		Long-term investments
Commercial Paper	$	12,364	$	-	$	(49	)	$	12,315	$	12,315	$	-
Corporate Bonds		55,201		-		(447	)		54,754		50,889		3,865
U.S. Government Agencies		999		-		(8	)		991		991		-
Total Investments	$	68,564	$	-	$	(504	)	$	68,060	$	64,195	$	3,865

	December 31, 2021
	(in thousands)
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Short-term investments		Long-term investments
Commercial Paper	$	50,705	$	-	$	(46	)	$	50,659	$	50,660	$	-
Corporate Bonds		67,239		1		(202	)		67,038		29,602		37,435
Total Investments	$	117,944	$	1	$	(248	)	$	117,697	$	80,262	$	37,435

The following table summarizes the contractual maturities of the Company’s available-for-sale investments:

	December 31, 2022
	(in thousands)
	Amortized Cost		Fair Value
Mature in less than one year	$	64,662	$	64,195
Mature in one to two years		3,902		3,865
Total	$	68,564	$	68,060

Actual maturities may differ from contractual maturities because certain borrowers have the right to call or prepay certain obligations. There were no sales of investments for the years ended December 31, 2022 or 2021, respectively. There were no realized gains or losses for the years ended December 31, 2022. The company recorded an immaterial amount of gross realized losses for the year ended December 31, 2021 related to the maturity of investments.