Stock Option Plan (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Stock Options Issued

	Directors									Officers
Grant date	May 3, 2019			April 24, 2020			May 7, 2021			May 3, 2019			April 24, 2020			May 7, 2021
Exercise price	$	55.71		$	50.00		$	43.89		$	55.71		$	50.00		$	43.89
Volatility	0.236			0.258			0.297			0.206			0.240			0.275
Expected life (years)	5.0			5.0			5.0			7.0			7.0			7.0
Assumed yield	3.75		%	3.80		%	4.96		%	3.80		%	3.85		%	4.97		%
Risk-free rate	2.33		%	0.36		%	0.77		%	2.43		%	0.51		%	1.24		%

Summary of Option Activity

The table below summarizes the option activity for the years 2021, 2020, and 2019:

	2021			2020			2019
	Shares	Weighted Average Exercise Price		Shares	Weighted Average Exercise Price		Shares	Weighted Average Exercise Price
Outstanding at January 1	1,502,670	$	52.86	1,309,614	$	53.38	1,114,169	$	52.40
Granted	250,500	43.89		238,000	50.00		260,000	55.71
Exercised	(64,920)	45.07		(10,749)	49.19		(57,055)	44.53
Expired/Forfeited	(87,000)	53.60		(34,195)	54.09		(7,500)	56.07
Outstanding December 31	1,601,250	51.73		1,502,670	52.86		1,309,614	53.38
Exercisable at December 31	1,098,500	53.22		971,545	53.01		763,614	52.43