Restructuring Costs And Other Charges (Restructuring Reserve Rollforward) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Restructuring Reserve [Roll Forward]
Restructuring Reserve, Beginning Balance	$ 15
Severance expense	2	$ 15
Transformation costs	8	$ 13
Other costs	38
Cash payments during the period	(49)
Restructuring Reserve, Ending Balance	$ 14

Consulting And Advisory Costs

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- Definition

Transformation Costs

+ References

No definition available.

+ Details

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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-Publisher FASB
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-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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