Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parentheticals) - $ / shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Retained Earnings [Member]
Common cash dividends declared, dividends per share (in dollars per share)	$ 0.05	$ 0.04
Common Stock [Member]
Proceeds from issuance of common stock, Employee Stock Purchase Plan, shares (in shares)	3,573	5,054
Proceeds from issuance of common stock, stock options exercised, shares (in shares)	44,284	46,020
Restricted stock awards, shares (in shares)	13,289	22,382
Exchange of common stock in connection with stock options exercised and restricted stock vested, shares (in shares)	6,772	19,628
Common cash dividends declared, dividends per share (in dollars per share)	$ 0.05	$ 0.04