Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 3,302	$ 1,182	$ 4,839	$ 2,182
Securities available for sale:
Unrealized holding (losses) gains on available-for-sale securities	(83)	1,552	(3,049)	1,567
Tax effect	16	(528)	641	(533)
Reclassification adjustment for net losses (gains) realized in net income	41	(22)	21	(31)
Tax effect	(8)	8	(4)	11
Total securities available-for-sale	(34)	1,010	(2,391)	1,014
Change in post-retirement obligations	111	(6)	103	(11)
Total other comprehensive income (loss)	77	1,004	(2,288)	1,003
Total comprehensive income	$ 3,379	$ 2,186	$ 2,551	$ 3,185

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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