Note 3 - Investments (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

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

	December 31, 2021
	Amortized Cost		Accrued Interest		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Obligations of U.S. Government and its agencies	$	4,043	$	17	$	-	$	(7	)	$	4,053
Corporate debt securities		4,294		40		-		(5	)		4,329
Certificates of deposit		1,652		8		-		(1	)		1,659
Total Investments	$	9.989	$	65	$	-	$	(13	)	$	10,041

	December 31, 2020
	Amortized Cost		Accrued Interest		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Obligations of U.S. Government and its agencies	$	24,986	$	14	$	3	$	(3	)	$	25,000
Certificates of deposit		3,225		11		3		−			3,239
Total Investments	$	28,211	$	25	$	6	$	(3	)	$	28,239

Debt Securities, Held-to-maturity [Table Text Block]

	2021		2020
Maturing in one year or less	$	3,212	$	28,239
Maturing after one year through two years		6,829		−
Total investments	$	10,041	$	28,239