Restructuring and Other Initiatives (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015 USD ($) employees	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Sep. 30, 2015 USD ($) employees
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 1,050	$ 1,051	$ 1,378	$ 1,431	$ 1,432	$ 1,349	$ 1,378
Additions, interest accretion and other	127	163	184	257	240	298
Payments	(168)	(174)	(437)	(232)	(239)	(208)
Revisions to estimates and effect of foreign currency	(61)	10	(74)	(82)	(2)	(7)
Ending Balance	948	1,050	1,051	1,374	1,431	1,432	948
GMNA [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance	485	438	459	460	471	497	459
Additions, interest accretion and other	9	65	9	9	10	10
Payments	(24)	(19)	(19)	(21)	(26)	(30)
Revisions to estimates and effect of foreign currency	(11)	1	(11)	(6)	5	(6)
Ending Balance	459	485	438	442	460	471	459
Remaining Payments Including Temporary Layoffs Benefits	351			352			351
GME [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance	393	440	751	699	590	503	751
Additions, interest accretion and other	5	9	127	173	179	191
Payments	(48)	(73)	(385)	(60)	(68)	(106)
Revisions to estimates and effect of foreign currency	(31)	17	(53)	(60)	(2)	2
Ending Balance	319	393	440	752	699	590	319
GME [Member] \| Germany Separation Programs [Member]
Restructuring Reserve [Roll Forward]
Restructuring and Related Cost, Cost Incurred to Date				716
GMIO [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance	164	171	166	264	358	333	166
Additions, interest accretion and other	58	54	37	70	27	48
Payments	(48)	(53)	(22)	(141)	(116)	(21)
Revisions to estimates and effect of foreign currency	(15)	(8)	(10)	(16)	(5)	(2)
Ending Balance	159	164	171	177	264	358	159
GMIO [Member] \| Separation Programs in Australia, Korea, Thailand, Indonesia, and Chevrolet Europe [Member]
Restructuring Reserve [Roll Forward]
Restructuring and Related Cost, Cost Incurred to Date	$ 663						$ 663
Employees Affected, Inception to Date \| employees	5,530						5,530
Expected Cost Remaining	$ 266						$ 266
GMIO [Member] \| Separation Programs in Australia, Korea, and Chevrolet Europe [Member]
Restructuring Reserve [Roll Forward]
Restructuring and Related Cost, Cost Incurred to Date				454
GMSA [Member]
Restructuring Reserve [Roll Forward]
Beginning Balance	8	2	2	8	13	16	2
Additions, interest accretion and other	55	35	11	5	24	49
Payments	(48)	(29)	(11)	(10)	(29)	(51)
Revisions to estimates and effect of foreign currency	(4)	0	0	0	0	(1)
Ending Balance	11	$ 8	$ 2	$ 3	$ 8	$ 13	11
GME and GMIO [Member] \| Change of business model in Russia [Member]
Restructuring Reserve [Roll Forward]
Expected Cost Remaining	$ 100						$ 100
Number of Dealers and Distributors Impacted, Inception to Date	300						300
Number of Employees Impacted, Inception to Date \| employees	1,130						1,130
Cost related to business withdrawal							$ 450
Noncontrolling Interest Adjustments							44
Cumulative Translation and Other Charges							182
Sales Incentives and Inventory Related Costs							144
Asset impairment charges							56
GME and GMIO [Member] \| Change of business model in Russia [Member] \| Dealer Restructuring and Other Contract Cancellation Costs [Member]
Restructuring Reserve [Roll Forward]
Additions, interest accretion and other							99
GME and GMIO [Member] \| Change of business model in Russia [Member] \| Employee Severance [Member]
Restructuring Reserve [Roll Forward]
Additions, interest accretion and other							$ 13

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The amount of temporary layoff benefits included in the remaining payments related to restructuring and other initiatives.

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Amount of any reversal and other adjustment made during the period to the amount of a previously accrued liability for a specified type of restructuring cost including foreign currency translation adjustments, excluding adjustments for costs incurred during the period and costs settled during the period.

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Charges related to sales incentives and inventory related costs.

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Amount of costs incurred to date for the specified restructuring cost.

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Amount of expected cost remaining for the specified restructuring cost.

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The number of positions eliminated as of the balance sheet date since inception of the restructuring plan(s).

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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