Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parentheticals) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-02 [Member]
Net change in fair value of available-for-sale securities during the period, taxes		$ 1,452
Cash dividends declared, per share (in dollars per share)	$ 0.60	$ 0.60
Issuance of shares of common stock pursuant to dividend reinvestment plan, shares (in shares)	83,442	91,471
Issuance of shares of common stock, shares (in shares)	7,151	7,202
Net change in fair value of available-for-sale securities during the period, taxes	$ 3,093

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

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