Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Net income	$ 11,940	$ 11,136	$ 8,824
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Dividends from subsidiary	3,787	3,546	3,529
Interest income	6	10	10
Interest expense	618	624	624
Non-interest expenses	495	417	435
Income before taxes and equity in undistributed net income of subsidiary	2,680	2,515	2,480
Income tax benefit	273	252	256
Income before equity in undistributed net income of subsidiary	2,953	2,767	2,736
Equity in undistributed net income of subsidiary	8,987	8,369	6,088
Net income	$ 11,940	$ 11,136	$ 8,824

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