Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Increase (Decrease) in Stockholders' Equity [Roll forward]
Other comprehensive income (loss), tax	$ (2,423)	$ 541	$ (4,358)	$ 2,930
Dividends declared per share (in dollars per share)	$ 0.40	$ 0.385	$ 1.17	$ 1.145

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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