Consolidated Statements of Income and Comprehensive Income (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Reclassifications for net unrealized investment gain/(losses) on available-for-sale securities	$ 130	$ (496)	$ 257	$ (655)
Reclassifications for employee benefit costs	1,124	1,661	3,372	4,982
Reclassifications for federal income tax benefit	$ 209	$ 453	$ 654	$ 1,184

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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