Note 7 - Stock Plans (Tables)

3 Months Ended

Mar. 31, 2023

Notes Tables

Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value [Table Text Block]

	March 31, 2023					March 31, 2022
				Weighted-					Weighted-
	Shares			average grant		Shares			average grant
	granted			date fair value		granted			date fair value
Director plan		-		$	-		18,000	(2)	$	49.85
Omnibus plan		18,000	(2)		49.43		16,520	(3)		49.85
Omnibus plan		17,684	(3)		49.43
Omnibus plan		50	(1)		49.43
Total		35,734		$	49.43		34,520		$	49.85

Nonvested Restricted Stock Shares Activity [Table Text Block]

	2012 & 2022 Stock incentive plans
	Director			Omnibus			Total			Weighted- average grant date fair value
Non-vested balance at December 31, 2022		23,872			38,614			62,486		$	51.46
Granted		-			35,734			35,734			49.43
Forfeited		-			-			-			-
Vested		(9,736	)		(10,713	)		(20,449	)		53.24
Non-vested balance at March 31, 2023		14,136			63,635			77,771		$	50.06

Share-Based Payment Arrangement, Stock Appreciation Right, Activity [Table Text Block]

	Awards		Weighted-average grant date fair value		Weighted-average remaining contractual term (years)
Outstanding December 31, 2022		87,133	$	9.69		4.5
Granted		-
Exercised		-
Forfeited		-
Outstanding March 31, 2023		87,133	$	9.69		4.3

Share-Based Payment Arrangement, Cost by Plan [Table Text Block]

	Three months ended March 31,
(dollars in thousands)	2023		2022
Stock-based compensation expense:
2012 Director stock incentive plan	$	114	$	109
2012 Omnibus stock incentive plan		141		165
2022 Omnibus stock incentive plan		156		-
Employee stock purchase plan		34		32
Total stock-based compensation expense	$	445	$	306

Share-Based Payment Arrangement, Nonvested Award, Cost [Table Text Block]

	As of
(dollars in thousands)	March 31, 2023
Unrecognized stock-based compensation expense:
2012 Director stock incentive plan	$	658
2012 Omnibus stock incentive plan		670
2022 Omnibus stock incentive plan		1,611
Total unrecognized stock-based compensation expense	$	2,939