Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Increase (Decrease) in Stockholders' Equity [Roll forward]
Other comprehensive income (loss), tax	$ 3,273	$ 3,403	$ (960)
Cash dividends declared (in dollars per share)	$ 1.53	$ 1.48	$ 1.38

Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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