Consolidated Statement of Changes in Stockholders' Equity (Unaudited) (Parentheticals)	3 Months Ended
Mar. 31, 2018 $ / shares shares
Retained Earnings [Member]
Dividend reinvestment and purchase plan, shares (in shares) \| shares	3,278
Stock-based compensation expense, shares (in shares) \| shares	1,990
Cash dividends, per share (in dollars per share) \| $ / shares	$ 0.33
Cash dividends, per share (in dollars per share) \| $ / shares	$ 0.33

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

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