Condensed Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (Parentheticals) - $ / shares	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Cash dividends per common share (in dollars per share)	$ 0.44	$ 0.36
Common Stock [Member]
Employee stock purchase plan (in shares)	755	682
Dividend reinvestment plan (in shares)	9,063	39,612
Stock option exercises (in shares)	7,000	20,000
Stock grants to directors (in shares)	11,171	11,712
Retained Earnings [Member]
Cash dividends per common share (in dollars per share)	$ 0.44	$ 0.36

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

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