Consolidated Statements of Income and Comprehensive Income (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Reclassifications for net unrealized gains on available-for-sale securities	$ (196)	$ 1,975	$ (159)	$ 5,380
Reclassification adjustment for employee benefit costs included in expense	1,661	1,352	3,321	2,704
Reclassifications adjustments - tax	$ 390	$ (219)	$ 731	$ (937)

Amount before 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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