Supplementary Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended								9 Months Ended	12 Months Ended
	Oct. 31, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total net sales and revenue		$ 37,715	$ 33,623	$ 36,984	$ 37,266	$ 39,896	$ 38,889	$ 37,383	$ 33,016		$ 145,588	$ 149,184	$ 135,725
Income (loss) from continuing operations		(4,903)	114	2,433	2,686	1,895	2,707	2,744	1,923		330	9,269	9,590
(Loss) from discontinued operations, net of tax		(277)	(3,096)	(770)	(69)	(120)	5	106	8		(4,212)	(1)	25
Net income (loss) attributable to stockholders		$ (5,151)	$ (2,981)	$ 1,660	$ 2,608	$ 1,835	$ 2,773	$ 2,866	$ 1,953		$ (3,864)	$ 9,427	$ 9,687
Basic earnings (loss) per common share – continuing operations (in dollars per share)		$ (3.46)	$ 0.08	$ 1.62	$ 1.78	$ 1.29	$ 1.79	$ 1.78	$ 1.25		$ 0.23	$ 6.12	$ 6.09
Basic (loss) per common share – discontinued operations (in dollars per share)		(0.19)	(2.14)	(0.51)	(0.05)	(0.08)	0.00	0.07	0.01		(2.88)	0.00	0.02
Diluted earnings (loss) per common share – continuing operations (in dollars per share)		(3.46)	0.08	1.60	1.75	1.27	1.76	1.74	1.23		0.22	6.00	5.89
Diluted earnings (loss) per common share – discontinued operations (in dollars per share)		$ (0.19)	$ (2.11)	$ (0.51)	$ (0.05)	$ (0.08)	$ 0.00	$ 0.07	$ 0.01		$ (2.82)	$ 0.00	$ 0.02
Tax expense related to tax reform legislation		$ 7,300									$ 7,300
Automotive [Member]
Segment Reporting Information [Line Items]
Automotive gross margin		$ 4,758	$ 3,955	$ 4,786	$ 5,081	$ 4,605	$ 5,391	$ 5,305	$ 4,405
Discontinued Operations [Member] | Opel/Vauxhall Business [Member]
Segment Reporting Information [Line Items]
(Loss) from discontinued operations, net of tax										$ (3,900)
Charge at closing										6,200
Income tax expense	$ 2,300									$ 2,300