Common Stock (Details) - USD ($) $ in Thousands	12 Months Ended			252 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2001
Common stock
Number of shares available to directors and employees for stock purchase or savings and investment plans (in shares)					250,000	700,000
Number of shares issued under employee savings and investment plan (in shares)	79,203			79,203
Number of shares available for future use under employee savings and investment plan (in shares)	170,797			170,797
Number of shares issued during period, employee benefit plan (in shares)	12,267	14,117	13,408
Number of shares registered with SEC for dividend reinvestment plan (in shares)							600,000
Number of shares issued during period, dividend reinvestment plan (in shares)	11,772	15,064	11,242	305,362
Number of shares for future use (in shares)	294,638
Proceeds from sale of common stock	$ 689	$ 670	$ 653
Capital Purchase Program
Common stock
Proceeds from sale of common stock	$ 689	$ 670	$ 653