Goodwill And Other Intangibles (Components Of Other Intangibles) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 5,382	$ 5,382
Accumulated Amortization	(3,479)	(3,319)
Net Carrying Amount	1,903	2,063
Customer Base [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	5,188	5,188
Accumulated Amortization	(3,450)	(3,294)
Net Carrying Amount	1,738	1,894
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	122	122
Net Carrying Amount	122	122
Royalty Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	72	72
Accumulated Amortization	(29)	(25)
Net Carrying Amount	$ 43	$ 47