Consolidated Statements of Stockholders' Equity (unaudited) (Parenthetical) - $ / shares	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Consolidated Statements of Stockholders' Equity (unaudited) [Abstract]
Cash dividends - per share (in dollars per share)	$ 0.44	$ 0.43
Purchase of treasury shares (in shares)	675,535	433,351
Net issuance of shares to employee benefit plans and other stock plans, including tax benefit (in shares)	237,824	222,326