Restructuring Costs And Other Charges (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Restructuring Costs And Other Charges
Restructuring Reserve	$ 11	$ 11		$ 25
Severance expense		8	$ 46
Transformation costs	$ 12	$ 12

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Period Type:	duration