Goodwill And Other Intangibles (Components Of Other Intangibles) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 5,382	$ 5,382
Accumulated Amortization	(4,018)	(3,888)
Net Carrying Amount	1,364	1,494
Customer Base [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	5,188	5,188
Accumulated Amortization	(3,975)	(3,848)
Net Carrying Amount	1,213	1,340
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	122	122
Net Carrying Amount	122	122
Royalty Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	72	72
Accumulated Amortization	(43)	(40)
Net Carrying Amount	$ 29	$ 32