Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Increase (Decrease) in Stockholders' Equity [Roll forward]
Other comprehensive income, tax	$ 541	$ 664	$ 2,930	$ 3,640
Dividends declared per share (in dollars per share)	$ 0.385	$ 0.38	$ 1.145	$ 1.10

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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