Condensed Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parentheticals) - $ / shares	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Cash dividends per common share (in dollars per share)	$ 0.22	$ 0.18
Retained Earnings [Member]
Cash dividends per common share (in dollars per share)	$ 0.22	$ 0.18
Common Stock [Member]
Employee stock purchase plan (in shares)	426	338
Dividend reinvestment plan (in shares)	4,624	35,319
Stock option exercises (in shares)	7,000	20,000
Stock grants to directors (in shares)		62

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

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