Consolidated Statements of Income and Comprehensive Income (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Income Statement [Abstract]
Reclassifications for net unrealized gains on available-for-sale securities	$ 37	$ (196)	$ 127	$ (159)
Reclassification adjustment for employee benefit costs included in expense	1,124	1,661	2,248	3,321
Reclassifications adjustments - tax	$ 229	$ 390	$ 445	$ 731

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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