Consolidated statements of comprehensive income (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net change in unrealized (loss) gain in available-for-sale, tax	$ (1,348)	$ 170	$ (4,667)	$ 1,577
Reclassification adjustment for (gain) loss on securities, tax	0	100	(2)	111
Net change in unrealized gain in hedging activities, tax	60	52	577	52
Reclassification adjustment for (gain) loss on hedging activities, tax	$ 23	$ 59	$ 22	$ 59

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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-Publisher FASB
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-Topic 220
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount of tax expense (benefit), before reclassification adjustments, related to 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 of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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-Publisher FASB
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