Note 7 - Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2023

Notes Tables

Marketable Securities [Table Text Block]

	March 31, 2023
(In thousands)	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value
Marketable securities
Corporate and municipal debt securities	$	4,976		79	$	(1	)	$	5,054

Investments Classified by Contractual Maturity Date [Table Text Block]

	March 31, 2023				December 31, 2022
(In thousands)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Due within one year	$	1,600	$	1,634	$	1,594	$	1,602
Due after one year through three years		3,376		3,420		3,356		3,371
Total	$	4,976	$	5,054	$	4,950	$	4,973