Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	$ 56,142	$ 54,451
Reclassification of net unrealized gains on equity securities from AOCI per ASU 2016-01	662
Net current-period other comprehensive income (loss)	(1,228)	915
Balance	58,277	57,185
Gains (Losses) on Cash Flow Hedges [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	37	17
Net current-period other comprehensive income (loss)	250	(4)
Balance	287	13
Unrealized Gains (Losses) on Available for Sale Securities [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	(37)	(765)
Reclassification of net unrealized gains on equity securities from AOCI per ASU 2016-01	(10)
Net current-period other comprehensive income (loss)	(1,478)	919
Balance	(1,525)	154
Supplemental Executive Retirement Plans [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	125	11
Balance	125	11
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Balance	125	(737)
Reclassification of net unrealized gains on equity securities from AOCI per ASU 2016-01	(10)
Balance	$ (1,113)	$ 178

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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