Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cash dividends declared, per share (in dollars per share)	$ 0.60	$ 0.55
Issuance of shares of common stock pursuant to dividend reinvestment plan, shares (in shares)	91,471	91,487
Issuance of shares of common stock, shares (in shares)	7,202	8,763
Net change in fair value of available-for-sale securities during the period, taxes	$ 1,452	$ 883

Aggregate dividends declared during the period for each share of common stock outstanding.

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