Stock Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Transactions of Stock Option Plans

The following table summarizes the transactions of the Company’s stock option plans for the three-year period ended December 31, 2021:

	Number of shares			Weighted- average exercise price
Options outstanding - December 31, 2018		376,900		$	28.95
Options granted		34,926			59.44
Options exercised		(66,969	)		29.29
Options forfeited		(7,525	)		38.81
Options outstanding - December 31, 2019		337,332		$	31.82
Options granted		41,807		$	62.76
Options exercised		(55,716	)		18.99
Options forfeited		(7,229	)		50.19
Options outstanding - December 31, 2020		316,194		$	37.75
Options exercised		(88,932	)	$	22.89
Options outstanding - December 31, 2021		227,262		$	43.56
Exercisable options —
December 31, 2019		271,252		$	27.17
December 31, 2020		235,829			30.82
December 31, 2021		170,484			38.31

Assumptions Used for Valuing Options Granted

The following assumptions were used for valuing options granted in the year ended December 31, 2020:

Per share fair value of options granted during the period	$	17.49
Risk-free interest rate		0.64	%
Dividend yield		1.05	%
Volatility factor		30.0	%
Weighted-average expected life in years		7.0

Schedule Share Based Compensation Intrinsic Value Of Stock Options Table Text Block

The following table summarizes the aggregate intrinsic value related to options exercised, outstanding and exercisable as of and for the years ended December 31:

	2021		2020		2019
	(In thousands)
Exercised	$	7,085	$	3,054	$	1,870
Outstanding		14,316		17,805		11,170
Exercisable		11,635		14,913		10,243

Schedule of Fair Value of Nonvested Shares

The fair value of nonvested shares is determined based on the market price of the shares on the grant date.

	Shares			Fair value per share
Nonvested at December 31, 2018		72,802		$	42.58
Granted		16,034			59.42
Vested		(19,227	)		30.08
Forfeited		(5,129	)		41.31
Nonvested at December 31, 2019		64,480		$	48.21
Granted		20,758			64.19
Vested		(25,044	)		39.87
Forfeited		(2,645	)		54.35
Nonvested at December 31, 2020		57,549		$	57.33
Granted		17,430			99.90
Vested		(16,528	)		49.31
Forfeited		(1,384	)		58.68
Nonvested at December 31, 2021		57,067		$	72.62

Summary of Performance Share Activity

A summary of performance share activity for the year ended December 31, 2021 is as follows:

	Performance Shares		Weighted Average Grant Date Fair Value
Nonvested at December 31, 2020		—	$	—
Granted		14,748		100.37
Adjustment for expected performance results		7,374		100.37
Nonvested at December 31, 2021		22,122	$	100.37