Discontinued Operations - Financial Information about Discontinued Operations (Details) - Discontinued Operations - Opel/Vauxhall Business - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss from discontinued operations	$ 0	$ 0	$ 70
Net sales and revenue	144	1,129	1,939
Purchases and expenses	392	825	1,422
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash payments	630	975	1,849
Cash receipts	$ 252	$ 1,408	$ 2,310

Discontinued Operation, Amount of Continuing Cash Payments after Disposal

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Discontinued Operation, Amount of Continuing Cash Receipts after Disposal

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4B
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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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Amount of operating income (loss) attributable to disposal group, including, but not limited to, discontinued operation.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
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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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