Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other comprehensive income (loss), net of tax:
Change in fair value of securities available for sale, tax	$ 43	$ (384)	$ 277
Reclassification adjustment for gain on securities available for sale, tax	176	0	0
Change in fair value of interest rate swap, tax	(36)	(1)	(107)
Change in unrecognized benefit obligation for Supplemental Executive Retirement Plan, tax	(4)	(27)	(26)
Other comprehensive income (loss), tax	$ 179	$ (412)	$ 144

Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount, before reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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Amount of tax expense (benefit) 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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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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