Consolidated Statements of Changes in Shareholders' Equity (USD $) In Millions, except Share data in Thousands, unless otherwise specified	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests [Member]
Beginning balance, Value at Dec. 31, 2010	$ 16,498		$ 3,472	$ 5,776	$ 7,935	$ (747)	$ 62
Beginning balance, Shares at Dec. 31, 2010			694,381
Add (Deduct):
Net income	932				898		34
Net change in other comprehensive income (loss)	391					391
Stock transactions:
In purchase acquisitions, Shares			26
In purchase acquisitions, Values	1			1
In connection with equity award, Shares			1,918
In connection with equity awards, Values	1		10	(9)
Shares repurchased in connection with equity awards, Shares			(642)
Shares repurchased in connection with equity awards, Value	(18)		(3)	(15)
In connection with dividend reinvestment plan, Shares			580
In connection with dividend reinvestment plan, Value	16		3	13
In connection with preferred stock offering	0
In connection with 401(k) plan, Shares			838
In connection with 401(k) plan, Value	23		4	19
Cash dividends declared on preferred stock	0
Cash dividends declared on common stock	(341)				(341)
Equity-based compensation expense	73			73
Other, net	(35)			(2)	1		(34)
Ending balance, Value at Sep. 30, 2011	17,541		3,486	5,856	8,493	(356)	62
Ending balance, Shares at Sep. 30, 2011			697,101
Beginning balance, Value at Dec. 31, 2011	17,480		3,486	5,873	8,772	(713)	62
Beginning balance, Shares at Dec. 31, 2011			697,143
Add (Deduct):
Net income	1,479				1,443		36
Net change in other comprehensive income (loss)	304					304
Stock transactions:
In purchase acquisitions, Shares			28
In purchase acquisitions, Values	1			1
In connection with equity awards, Shares			2,936
In connection with equity awards, Values	29		15	14
Shares repurchased in connection with equity awards, Shares			(566)
Shares repurchased in connection with equity awards, Value	(17)		(3)	(14)
In connection with preferred stock offering	1,679	1,679
Cash dividends declared on preferred stock	(33)				(33)
Cash dividends declared on common stock	(421)				(421)
Equity-based compensation expense	79			79
Other, net	(48)			(3)			(45)
Ending balance, Value at Sep. 30, 2012	$ 20,532	$ 1,679	$ 3,498	$ 5,950	$ 9,761	$ (409)	$ 53
Ending balance, Shares at Sep. 30, 2012			699,541