Note 18 - Share-based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	2021			2020			2019
Expected volatility		34 - 35	%		27 - 32	%		26 - 27	%
Weighted-average expected volatility		35	%		27	%		26	%
Expected dividend yield		1.3 - 1.4	%		1.3	%		1.2 - 1.4	%
Weighted-average expected dividend yield		1.4	%		1.3	%		1.2	%
Expected term, in years		5			5			5
Risk-free interest rate		0.8 - 0.9	%		0.3 - 1.3	%		1.6 - 2.5	%

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

	Shares			Weighted-Average Exercise Price
Outstanding at beginning of year		990,663		$	62.90
Granted		73,274			79.14
Exercised		(147,890	)		51.88
Forfeited		(5,912	)		64.42
Expired		(863	)		73.72
Outstanding at end of year		909,272		$	65.98
Exercisable at end of year		743,371		$	64.03

Nonvested Restricted Stock Shares Activity [Table Text Block]

	Shares			Weighted-Average Grant Date Fair Value
Nonvested at beginning of year		94,043		$	55.81
Granted		16,863			79.34
Vested		(19,332	)		59.81
Forfeited		—			—
Nonvested at end of year		91,574		$	59.30

Schedule of Nonvested Performance-based Units Activity [Table Text Block]

	Shares			Weighted-Average Grant Date Fair Value
Nonvested at beginning of year		124,219		$	69.68
Granted		57,195			78.39
Vested		(43,621	)		67.88
Forfeited		(7,441	)		72.25
Nonvested at end of year		130,352		$	73.96

Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]

	Shares			Weighted-Average Grant Date Fair Value
Nonvested at beginning of year		97,485		$	64.95
Granted		61,121			82.44
Vested		(54,752	)		59.28
Forfeited		(12,883	)		79.44
Nonvested at end of year		90,971		$	78.06