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	$ 7,282	$ 8,835	$ 4,350
Securities available for sale:
Unrealized holding gains (losses) on available-for-sale securities	6,023	(2,426)	2,153
Tax effect	(1,265)	510	(733)
Reclassification adjustment for net losses (gains) realized in net income	44	21	(7)
Tax effect	(9)	(4)	3
Total securities available-for-sale	4,793	(1,899)	1,416
Change in post-retirement obligations	31	68	14
Total other comprehensive income (loss)	4,824	(1,831)	1,430
Total comprehensive income	$ 12,106	$ 7,004	$ 5,780

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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