Consolidated Statements of Changes In Stockholders' Equity Parenthetical - $ / shares	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Statement of Stockholders' Equity [Abstract]
Cash Dividends Paid, per Share, in dollars per share	$ 0.50	$ 0.485
Exercised, in shares	79,001	33,062
Shares Issued Under Directors Stock Plan, in shares	2,705	3,927
Shares Issued Under Employee Stock Purchase Plan, in shares	7,613	7,300
Shares Issued for Dividend Reinvestment Plans - Shares	24,305	24,999
Purchase of Treasury Stock, in shares	40,009	56,908