Consolidated Statements of Income and Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Reclassifications for unrealized net gains on available-for-sale securities	$ (784)	$ 6,390	$ 4,520
Reclassifications for employee benefit costs	6,642	5,408	5,486
Reclassifications adjustments tax	$ 1,559	$ (344)	$ 338

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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