Common and Preferred Stock Common and Preferred Stock (Schedule of Activity in the Outstanding Shares of the Company's Common Stock) (Details) - Common Stock [Member] - shares shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Common Stock [Roll Forward]
Shares outstanding, beginning balance	106,615	101,461	97,226
Awards and sales under employee and director plans	416	403	397
5% stock dividend	5,305	5,078	4,831
Other purchases of treasury stock	(1,194)	(315)	(959)
Other	(13)	(12)	(34)
Shares outstanding, ending balance	111,129	106,615	101,461