Consolidated Statements of Equity (USD $) In Millions, unless otherwise specified	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Reinvested Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Noncontrolling Interest [Member]
Balance at Dec. 31, 2011	$ 9,208	$ 237	$ 304	$ 10,107	$ 13,552	$ (8,750)	$ (6,727)	$ 485
Acquisitions of a noncontrolling interest in consolidated subsidiaries	(388)			(2)				(386)
Net income	2,780				2,755			25
Other comprehensive income (loss)	132					104		28
Common dividends	(1,654)				(1,593)			(61)
Preferred dividends	(10)				(10)
Common Stock
Issued - compensation plans	631		4	627
Repurchased	(400)						(400)
Retired	0		(2)	(77)	(321)		400
Balance at Dec. 31, 2012	10,299	237	306	10,655	14,383	(8,646)	(6,727)	91
Sale of a majority interest in a consolidated subsidiary	(34)							(34)
Acquisitions of a noncontrolling interest in consolidated subsidiaries	4			4
Net income	4,862				4,848			14
Other comprehensive income (loss)	3,203					3,205		(2)
Common dividends	(1,670)				(1,658)			(12)
Preferred dividends	(10)				(10)
Common Stock
Issued - compensation plans	632		4	628
Repurchased	(1,000)						(1,000)
Retired	0		(6)	(215)	(779)		1,000
Balance at Dec. 31, 2013	16,286	237	304	11,072	16,784	(5,441)	(6,727)	57
Sale of a majority interest in a consolidated subsidiary	(5)							(5)
Net income	3,636				3,625			11
Other comprehensive income (loss)	(3,265)					(3,266)		1
Common dividends	(1,701)				(1,695)			(6)
Preferred dividends	(10)				(10)
Common Stock
Issued - compensation plans	437		3	434
Repurchased	(2,000)						(2,000)
Retired	0		(9)	(332)	(1,659)		2,000
Balance at Dec. 31, 2014	$ 13,378	$ 237	$ 298	$ 11,174	$ 17,045	$ (8,707)	$ (6,727)	$ 58