Note 19 - Equity Incentive Plan (Tables)

12 Months Ended

Dec. 31, 2022

Notes Tables

Schedule of Share-Based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

	2022			2021			2020
Expected dividends		1.85	%		1.53	%		1.56	%
Expected term (in years)		7.78			9.13			7.38
Expected stock price volatility		37	%		36	%		31	%
Risk-free rate		3.03	%		1.45	%		0.52	%

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

	2022					2021					2020
				Weighted Average					Weighted Average					Weighted Average
	Shares			Exercise Price		Shares			Exercise Price		Shares			Exercise Price
Outstanding at beginning of year		357,254		$	50.18		284,591		$	43.71		273,039		$	41.19
Granted		117,665			64.13		121,830			61.48		43,833			55.72
Exercised		(58,841	)		43.27		(48,867	)		40.76		(24,881	)		37.84
Forfeited or expired		(1,300	)		45.50		(300	)		37.60		(7,400	)		41.70
Outstanding at end of year		414,778		$	55.13		357,254		$	50.18		284,591		$	43.71
Options and cash-settled SARs exercisable at year end		167,918		$	46.09		159,560		$	41.93		151,695		$	40.89

Share-Based Payment Arrangement, Option, Exercise Price Range [Table Text Block]

	Options and Cash-Settled SARs Outstanding						Options and Cash-Settled SARs Exercisable
Range of Exercise Prices	Number Outstanding at 12/31/22		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)		Number Outstanding at 12/31/22		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (In Years)
$32.81 - $51.00		132,266	$	41.55		4.00		123,166	$	41.33		3.96
$51.25 - $66.70		282,512	$	61.49		8.48		44,752	$	59.09		7.00
		414,778						167,918
Aggregate intrinsic value (in thousands)	$	5,275					$	3,658

Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]

	Restricted Stock Shares
	Shares			Weighted Average Grant-Date Fair Value
Outstanding at December 31, 2021		1,250		$	62.10
Granted		450			66.70
Vested		(625	)		62.10
Forfeited		—			—
Outstanding at December 31, 2022		1,075		$	64.03