Share-Based Compensation (Schedule Of Share-Based Compensation Expense Included In The Consolidated Statements Of Comprehensive Earnings) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 20	$ 45
Related income tax benefit		9
G&A [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 20	23
Restructuring and Transaction Costs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Accelerated share-based compensation expense		$ 22

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 718
-SubTopic 10
-Section 50
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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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