Nature of Operations, Basis of Presentation and Change in Accounting Principle (Details 2) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Jan. 01, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Statement of Results of Operations
Cost of goods sold		$ 7,633	$ 6,527	$ 22,160	$ 20,768
Selling, general and administrative expenses		1,237	992	3,571	3,203
Research and development expenses		455	453	1,326	1,429
Other operating (income) expenses		348	560	1,780	1,356
Total operating costs		9,836	8,679	29,321	27,203
Operating profit		1,577	481	3,245	1,760
Other income (expense)		64	28	88	112
Consolidated profit before taxes		1,523	383	2,971	1,487
Provision (benefit) for income taxes		470	96	921	372
Profit of consolidated companies		1,053	287	2,050	1,115
Profit of consolidated and affiliated companies		1,061	283	2,058	1,108
Profit	[1]	$ 1,059	$ 283	$ 2,053	$ 1,104
Profit per common share (in dollars per share)		$ 1.79	$ 0.48	$ 3.48	$ 1.89
Profit per common share - diluted (in dollars per share)	[2]	$ 1.77	$ 0.48	$ 3.44	$ 1.88
Statement of Comprehensive Income
Profit of consolidated and affiliated companies		$ 1,061	$ 283	$ 2,058	$ 1,108
Foreign currency translation, net of tax		248	137	719	442
Total other comprehensive income (loss), net of tax		238	106	806	508
Comprehensive income		1,299	389	2,864	1,616
Comprehensive income attributable to stockholders		1,297	389	2,859	1,612
Statement of Financial Position
Noncurrent deferred and refundable income taxes		2,845		2,845				$ 2,790
Liability for postemployment benefits		8,973		8,973				9,357
Profit employed in the business		28,530		28,530				27,377
Accumulated other comprehensive income (loss)		(1,233)	(1,527)	(1,233)	(1,527)	$ (1,471)		(2,039)	$ (1,633)	$ (2,035)
Statement of Shareholders' Equity
Profit of consolidated and affiliated companies		1,061	283	2,058	1,108
Foreign currency translation, net of tax		248	137	719	442
Pension and other postretirement benefits, net of tax				(4)	90
Total stockholders' equity		15,697	15,715	15,697	15,715		$ 13,228	$ 13,213		$ 14,885
Statement of Cash Flow
Profit of consolidated and affiliated companies		$ 1,061	$ 283	2,058	1,108
Adjustments for non-cash items: Other				592	640
Other assets - net				(137)	(141)
Other liabilities - net				$ (325)	$ (279)

[1] 1 Profit attributable to common shareholders.

[2] 2 Diluted by assumed exercise of stock-based compensation awards using the treasury stock method.