Divestitures, Decommissioning and Restructuring Activities (Schedule of Restructuring and Employee Related Costs) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Reserve [Roll Forward]
Additions (a)	$ 1	$ 146	$ 1	$ 158
Employee severance
Restructuring Reserve [Roll Forward]
Beginning employee-related obligations			6	27
Additions (a)			1	156
Cash payments			(6)	(89)
Ending employee-related obligations	$ 1	$ 94	$ 1	$ 94

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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
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