Note 5 - Investments, Available-for-sale (Tables)

6 Months Ended

Jun. 30, 2023

Notes Tables

Debt Securities, Available-for-Sale [Table Text Block]

	June 30, 2023
	(in thousands)
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Short-term investments		Long-term investments
Commercial Paper	$	2,986	$	-	$	(5	)	$	2,981	$	2,981	$	-
Corporate Bonds		16,025		-		(83	)		15,942		15,942		-
U.S. Treasuries		12,386		-		(5	)		12,381		12,381		-
U.S. Government Agencies		999		-		(6	)		993		993		-
Total Investments	$	32,396	$	-	$	(99	)	$	32,297	$	32,297	$	-

	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