Discontinued Operations Narrative (Details) - Discontinued Operations [Member] - Opel/Vauxhall Business [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total net sales and revenue transactions with discontinued operations	$ 427	$ 607
Purchases and expenses with discontinued operations	192	476
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash payments used in operating activities	279	426
Cash receipts provided by operating activities	$ 581	$ 811

Discontinued Operation, Amount of Continuing Cash Payments after Disposal

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- Definition

Discontinued Operation, Amount of Continuing Cash Receipts after Disposal

+ References

No definition available.

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- Definition

Amount of expense in continuing operations related to continuing involvement in a discontinued operation after the disposal that before the disposal was eliminated as intra-entity transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721665-107760

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- Definition

Amount of revenue in continuing operations related to continuing involvement in a discontinued operation after disposal that before the disposal was eliminated as intra-entity transactions.

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- Definition

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.

+ References

No definition available.

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