Shareholders' Equity (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017		Mar. 31, 2016	Jan. 01, 2017
Shareholders' equity activity [Roll Forward]
Balance at beginning of period		$ 9,448		$ 15,495
Effect of early adoption of income tax consequences of intra-entity transfer of assets other than inventory		(384)	[1]		$ (384)
Stock plans		120		126
Payments of dividends to shareholders		(156)		(154)
Other		(9)		12
Comprehensive income (loss)		(30)		(2,419)
Balance at end of period		8,989		13,060
Company shareholders' equity
Shareholders' equity activity [Roll Forward]
Balance at beginning of period		9,409		15,462
Effect of early adoption of income tax consequences of intra-entity transfer of assets other than inventory	[1]	(384)
Stock plans		120		126
Payments of dividends to shareholders		(156)		(154)
Other		(8)		(6)
Comprehensive income (loss)		(30)		(2,413)
Balance at end of period		8,951		13,015
Noncontrolling interest in consolidated subsidiaries
Shareholders' equity activity [Roll Forward]
Balance at beginning of period		39		33
Effect of early adoption of income tax consequences of intra-entity transfer of assets other than inventory	[1]	0
Stock plans		0		0
Payments of dividends to shareholders		0		0
Other		(1)		18
Comprehensive income (loss)		0		(6)
Balance at end of period		$ 38		$ 45

[1] Represents a cumulative-effect adjustment to retained earnings upon our adoption of a new accounting standards update on the income tax consequences of intra-entity transfers of assets other than inventory which was effective January 1, 2017. See Note 9 for further information.