Commitments and Contingencies Ignition Switch Recall Compensation Program (Details) Number in Millions, $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2014	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Recalls - Ignition Switch [Member]
Loss Contingencies [Line Items]
Vehicles recalled	2.6
Ignition Switch Recall Compensation Program [Member]
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period		$ 66	$ 315
Provisions		0	225
Payments		(53)	(350)
Balance at end of period		$ 13	$ 190

Number of vehicles recalled

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Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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