Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Net sales and revenue	$ 42,372	$ 38,180	$ 79,637	$ 73,892
Income (loss) before automotive interest and taxes-adjusted	3,947	2,871	6,602	4,953
Adjustments	(115)	(1,110)	(175)	(1,657)
Income before income taxes	3,721	1,717	6,211	3,154
Income tax expense	(871)	(577)	(1,430)	(1,106)
Net (income) loss attributable to noncontrolling interests	16	(23)	38	14
Net income attributable to common stockholders	2,866	1,117	4,819	2,062
Total assets	210,449	185,453	210,449	185,453	$ 194,338
Depreciation and amortization	2,491	1,702	4,713	3,240
Impairment Charges	88	468	158	687
Automotive [Member]
Segment Reporting Information [Line Items]
Automotive interest income	52	41	96	90
Automotive interest expense	(147)	(108)	(274)	(218)
Group [Member] \| Automotive [Member] \| Operating segments [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	40,089	36,670	75,284	71,034
Income (loss) before automotive interest and taxes-adjusted	3,687	2,648	6,120	4,519
Adjustments	(115)	(1,110)	(175)	(1,657)
Total assets	134,476	131,993	134,476	131,993
Depreciation and amortization	1,365	1,208	2,657	2,401
Impairment Charges	88	468	158	687
Group [Member] \| Automotive [Member] \| Operating segments [Member] \| GMNA [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	30,195	26,481	56,658	51,157
Income (loss) before automotive interest and taxes-adjusted	3,647	2,780	5,943	4,962
Adjustments	0	(3)	0	29
Total assets	99,189	89,606	99,189	89,606
Depreciation and amortization	1,072	939	2,093	1,865
Impairment Charges	29	94	41	269
Group [Member] \| Automotive [Member] \| Operating segments [Member] \| GMNA [Member] \| Lyft [Member]
Segment Reporting Information [Line Items]
Cost Method Investment	500		500
Group [Member] \| Automotive [Member] \| Operating segments [Member] \| GME [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	5,386	4,987	10,067	9,436
Income (loss) before automotive interest and taxes-adjusted	137	(45)	131	(284)
Adjustments	0	(17)	0	(354)
Total assets	14,453	11,090	14,453	11,090
Depreciation and amortization	115	80	218	160
Impairment Charges	28	38	54	79
Group [Member] \| Automotive [Member] \| Operating segments [Member] \| GMIO [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	2,825	3,053	5,504	6,165
Income (loss) before automotive interest and taxes-adjusted	169	349	548	720
Adjustments	0	(295)	0	(387)
Total assets	21,318	21,049	21,318	21,049
Depreciation and amortization	105	113	213	221
Impairment Charges	31	302	63	305
Group [Member] \| Automotive [Member] \| Operating segments [Member] \| GMSA [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	1,638	2,109	2,981	4,201
Income (loss) before automotive interest and taxes-adjusted	(121)	(144)	(188)	(358)
Adjustments	0	(720)	0	(720)
Total assets	7,670	8,269	7,670	8,269
Depreciation and amortization	70	73	127	149
Impairment Charges	0	34	0	34
Group [Member] \| Automotive [Member] \| Corporate [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	45	40	74	75
Income (loss) before automotive interest and taxes-adjusted	(145)	(292)	(314)	(521)
Adjustments	(115)	(75)	(175)	(225)
Total assets	21,438	21,815	21,438	21,815
Depreciation and amortization	3	4	8	8
Impairment Charges	0	0	0	0
Group [Member] \| Automotive [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Total assets	(29,592)	(19,836)	(29,592)	(19,836)
Depreciation and amortization	0	(1)	(2)	(2)
Impairment Charges	0	0	0	0
Group [Member] \| GM Financial [Member] \| Operating segments [Member] \| GM Financial Segment [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	2,292	1,515	4,367	2,869
Income (loss) before automotive interest and taxes-adjusted	266	225	491	439
Adjustments	0	0	0	0
Total assets	77,724	55,288	77,724	55,288
Depreciation and amortization	1,126	494	2,056	839
Impairment Charges	0	0	0	0
InterGroup Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	(9)	(5)	(14)	(11)
Income (loss) before automotive interest and taxes-adjusted	(6)	(2)	(9)	(5)
Adjustments	0	0	0	0
Total assets	(1,751)	(1,828)	(1,751)	(1,828)
Depreciation and amortization	0	0	0	0
Impairment Charges	$ 0	$ 0	$ 0	$ 0

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