v3.3.0.814

Commitments and Contingencies Ignition Switch Recall Compensation Program (Details) $ in Millions	3 Months Ended				6 Months Ended	9 Months Ended			18 Months Ended	19 Months Ended
	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Jan. 31, 2015	Sep. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014	Sep. 30, 2015 USD ($)	Oct. 16, 2015 USD ($)
Loss Contingencies [Line Items]
Vehicles recalled								34,000,000
Ignition switch recall compensation program [Member]
Loss Contingencies [Line Items]
Number of Claims Filed					4,343
Number of Eligible Claims						399			399
Compensation Program Activity [Roll Forward]
Beginning balance		$ 315	$ 0			$ 315	$ 0		$ 0	$ 0
Additions	$ 75	$ 150	$ 400			225	400		625
Payments						(350)	(85)
Ending balance				$ 0		$ 190	$ 315		$ 190
Ignition switch recall compensation program [Member] | Subsequent Event [Member]
Loss Contingencies [Line Items]
Number of claims settled										300
Compensation Program Activity [Roll Forward]
Payments										$ (453)
Recalls - Ignition Switch [Member]
Loss Contingencies [Line Items]
Vehicles recalled				2,600,000

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