Restructuring Costs And Other Charges (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Restructuring Costs And Other Charges
Restructuring Reserve	$ 35		$ 18
Severance expense	15
Transformation costs	13
Restructuring charges	$ 28	$ 4

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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-Publisher FASB
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Period Type:	duration