Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Consolidated Statements of Stockholders' Equity [Abstract]
Restricted stock compensation, shares		18,079
Exercise of stock options, shares	9,264
Cash dividends- common stock per share	$ 0.21	$ 0.21
Sale of treasury shares to 401(k), shares	8,366	7,111
Sale of treasury shares to deferred compensation plan, shares	4,313	4,404