Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Statement of Stockholders' Equity [Abstract]
Cash dividends declared (in dollars per share)	$ 0.92	$ 0.88
Exercise of stock options (in shares)	25,147	16,639
Stock issued during period (in shares)	0	440,604
Purchase of treasury shares (in shares)	214,327	0