Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Net sales and revenue	$ 41,200	$ 37,265
Earnings (loss) before automotive interest and taxes-adjusted	3,395	2,655
Adjustments	0	(60)
Net (income) loss attributable to noncontrolling interests	(9)	22
Income before income taxes	3,317	2,490
Income tax expense	(700)	(559)
Net income attributable to common stockholders	2,608	1,953
Equity in net assets of nonconsolidated affiliates	9,416	9,640	$ 8,996
Total assets	230,793	203,618	$ 221,690
Depreciation and amortization	2,825	2,222
Impairment charges	58	70
Equity income	555	560
Automotive [Member]
Segment Reporting Information [Line Items]
Automotive interest income	57	44
Automotive interest expense	(144)	(127)
Group [Member] \| Operating Segments [Member] \| Automotive [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	38,456	35,195
Earnings (loss) before automotive interest and taxes-adjusted	3,137	2,433
Adjustments	0	(60)
Equity in net assets of nonconsolidated affiliates	8,418	8,651
Total assets	137,641	132,520
Depreciation and amortization	1,386	1,292
Impairment charges	58	70
Equity income	508	524
Group [Member] \| Operating Segments [Member] \| GMNA [Member] \| Automotive [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	29,302	26,463
Earnings (loss) before automotive interest and taxes-adjusted	3,416	2,296
Adjustments	0	0
Equity in net assets of nonconsolidated affiliates	77	89
Total assets	105,784	94,496
Depreciation and amortization	1,100	1,021
Impairment charges	15	12
Equity income	5	6
Group [Member] \| Operating Segments [Member] \| GME [Member] \| Automotive [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	4,501	4,681
Earnings (loss) before automotive interest and taxes-adjusted	(201)	(6)
Adjustments	0	0
Equity in net assets of nonconsolidated affiliates	0	0
Total assets	14,529	14,939
Depreciation and amortization	95	103
Impairment charges	37	26
Equity income	0	0
Group [Member] \| Operating Segments [Member] \| GMIO [Member] \| Automotive [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	2,520	2,679
Earnings (loss) before automotive interest and taxes-adjusted	319	379
Adjustments	0	0
Equity in net assets of nonconsolidated affiliates	8,339	8,560
Total assets	20,537	21,234
Depreciation and amortization	118	108
Impairment charges	1	32
Equity income	503	518
Group [Member] \| Operating Segments [Member] \| GMSA [Member] \| Automotive [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	1,959	1,343
Earnings (loss) before automotive interest and taxes-adjusted	(115)	(67)
Adjustments	0	0
Equity in net assets of nonconsolidated affiliates	2	2
Total assets	7,826	7,340
Depreciation and amortization	73	57
Impairment charges	0	0
Equity income	0	0
Group [Member] \| Operating Segments [Member] \| GM Financial [Member] \| GM Financial [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	2,879	2,075
Earnings (loss) before automotive interest and taxes-adjusted	260	225
Adjustments	0	0
Equity in net assets of nonconsolidated affiliates	998	989
Total assets	94,684	72,907
Depreciation and amortization	1,439	930
Impairment charges	0	0
Equity income	47	36
Group [Member] \| Corporate [Member] \| Automotive [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	174	29
Earnings (loss) before automotive interest and taxes-adjusted	(282)	(169)
Adjustments	0	(60)
Equity in net assets of nonconsolidated affiliates	0	0
Total assets	26,823	19,801
Depreciation and amortization	1	5
Impairment charges	5	0
Equity income	0	0
Group [Member] \| Corporate [Member] \| Automotive [Member] \| Ignition Switch Recall Litigations [Member]
Segment Reporting Information [Line Items]
Charges for legal related matters		60
Group [Member] \| Eliminations [Member] \| Automotive [Member]
Segment Reporting Information [Line Items]
Equity in net assets of nonconsolidated affiliates	0	0
Total assets	(37,858)	(25,290)
Depreciation and amortization	(1)	(2)
Impairment charges	0	0
Equity income	0	0
Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales and revenue	(135)	(5)
Earnings (loss) before automotive interest and taxes-adjusted	(2)	(3)
Adjustments	0	0
Equity in net assets of nonconsolidated affiliates	0	0
Total assets	(1,532)	(1,809)
Depreciation and amortization	0	0
Impairment charges	0	0
Equity income	$ 0	$ 0

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