Consolidated Statements of Income and Comprehensive Income (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Reclassifications for net unrealized gains on available-for-sale securities	$ (496)	$ 419	$ (655)	$ 5,799
Reclassification adjustment for employee benefit costs included in expense	1,661	1,352	4,982	4,056
Reclassifications adjustments - tax	$ 453	$ 327	$ 1,184	$ (610)

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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