Comprehensive Income - Reclassifications (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Comprehensive Income
Gain on sale of securities	$ 326	$ 183
Salaries and benefits	(10,473)	(9,962)
Income before income taxes	3,291	2,295
Income tax expense	(697)	(721)
Net income	2,594	1,574
Amount reclassified from AOCI
Comprehensive Income
Net income	192	74
Available-for-sale securities \| Amount reclassified from AOCI
Comprehensive Income
Gain on sale of securities	326	183
Income before income taxes	326	183
Income tax expense	(88)	(73)
Net income	238	110
Defined benefit pension plan items \| Amount reclassified from AOCI
Comprehensive Income
Salaries and benefits	(77)	(60)
Income before income taxes	(77)	(60)
Income tax expense	31	24
Net income	$ (46)	$ (36)

This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 7
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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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