Common and Preferred Stock (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Common: Par value $.25, 600,000,000 shares authorized
Outstanding - January 1	256,869,000	256,544,000	259,276,000
Issued for stock option exercises and other benefit plans	2,761,000	1,110,000	2,751,000
Repurchase of common stock	(15,663,000)	(785,000)	(5,483,000)
Outstanding - December 31	243,967,000	256,869,000	256,544,000
Treasury stock	52,178,000	39,276,000	39,601,000
Issued - December 31	296,145,000	296,145,000	296,145,000
Common Stock, par value and shares authorized
Common stock, par value per share	$ 0.25	$ 0.25	$ 0.25
Common stock shares authorized	600,000,000	600,000,000	600,000,000
Preferred Stock [Abstract]
Preferred Stock, Shares Authorized	25,000,000	25,000,000	25,000,000
Preferred Stock, Par Value Per Share	$ 1	$ 1	$ 1
Preferred Stock, Shares Outstanding	0	0	0