Consolidated Statements of Stockholders' Equity (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Consolidated Statements of Stockholders' Equity [Abstract]
Restricted stock compensation, shares		18,079
Exercise of stock options, shares	9,132
Cash dividends- common stock per share	$ 0.14	$ 0.14
Sale of treasury shares to 401(k), shares	5,390	4,288
Sale of treasury shares to deferred compensation plan, shares	2,773	2,566