Shares and Stockholders' Equity (Changes In Common stock (Number Of Shares)) (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Changes In Preferred And Common Stock Number Of Shares [Line Items]
Balance as of beginning-of-period			218,090,114
Balance as of end-of-period	214,776,806		214,776,806
Common stock as of End-of-period:
Basic basis	214,776,806	219,544,618	214,776,806	219,544,618
Diluted basis	217,390,897	222,701,021	217,390,897	222,701,021
Common Stock [Member]
Changes In Preferred And Common Stock Number Of Shares [Line Items]
Balance as of beginning-of-period	217,294,051	222,237,262	218,090,114	226,335,105
Stock issued for exercise of warrants	97,076	2,464	119,942	337,394
Stock compensation/issued for benefit plans	38,642	139,179	675,608	1,600,465
Retirement/cancellation of shares	(2,652,963)	(2,834,287)	(4,108,858)	(8,728,346)
Balance as of end-of-period	214,776,806	219,544,618	214,776,806	219,544,618