Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Federal corporate tax rate	21.00%		28.10%
Accounting Standards Update 2018-02 [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Reclassification of net losses and past service liability for defined benefit plan			$ 316
Reclassification of unrealized gains on available for sale securities from accumulated other comprehensive loss to retained earnings			$ (57)
Federal corporate tax rate	21.00%	34.00%

Amount, after tax, of reclassification adjustment from accumulated other comprehensive (income) loss for net periodic benefit cost (credit) of defined benefit plan.

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