Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Consolidated Statements of Changes in Stockholders' Equity [Abstract]
Restricted stock compensation expense, shares	4,908
Exercise of stock options, shares	2,338	9,132
Cash dividends- common stock per share	$ 0.14	$ 0.14
Sale of treasury shares to 401(k), shares	5,658	4,288
Sale of treasury shares to deferred compensation plan, shares	2,877	2,566