Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 6,820	$ 6,135	$ 2,496
Other comprehensive income (loss), net of tax:
Change in fair value of securities available for sale, net of tax, $(586), $43, and $(384), respectively	2,204	(161)	735
Reclassification adjustment for gain on securities available for sale, net of tax, $17, $176, and $0, respectively	(62)	(662)
Change in fair value of interest rate swap, net of tax, $66, $(36), and $(1), respectively	(250)	135	14
Change in unrecognized benefit obligation for Supplemental Executive Retirement Plan, net of tax, $(4), $(4) and $(27), respectively	17	15	92
Total other comprehensive income (loss), net of tax, $(507), $179, and $(412), respectively	1,909	(673)	841
Total comprehensive income	$ 8,729	$ 5,462	$ 3,337

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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