Cash And Cash Equivalents Net Change in Operating Assets and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Supplemental Cash Flow Elements [Abstract]
Accounts receivable	$ (302)	$ 907
Accounts receivable from related companies	(38)	102
Inventories	49	186
Other current assets	99	(46)
Other non-current assets, net	(10)	46
Accounts payable	321	(810)
Accounts payable to related companies	(10)	(163)
Accrued and other current liabilities	(406)	524
Other non-current liabilities	(31)	20
Derivative assets and liabilities, net	(13)	(9)
Net change in operating assets and liabilities, net of effects of acquisitions	$ 341	$ (757)

The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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- Definition

The increase (decrease) during the reporting period in the aggregate amount of expenses incurred but not yet paid.

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- Definition

The aggregate increase (decrease) during the reporting period in the amount due from the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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The increase (decrease) during the reporting period in the aggregate amount of obligations to be paid to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entities' management; an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

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The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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- Definition

Amount of increase (decrease) in current assets classified as other.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

Amount of increase (decrease) in deferred obligations classified as other.

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- Definition

Amount of increase (decrease) in noncurrent assets classified as other.

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- Definition

Amount of increase (decrease) in fair value of financial instruments other than those that are purchased and held principally for the purpose of hedging or mitigating market risk, credit risk, legal risk, operational risk and other types of risk.

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No definition available.

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