Parent Company Financial Statements (Parent Company Condensed Income Statements) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other income	$ 362	$ 299	$ 194
Interest expense	891	1,060	1,378
Other expenses	5,837	5,828	5,802
Income (loss) before income taxes	3,124	2,792	1,628
Income tax benefit	(1,395)	(764)	(296)
Net income	1,729	2,028	1,332
Noncontrolling interests	50	49	43
Dividends on preferred stock	117	63
Net income available to common shareholders	1,562	1,916	1,289
Parent Company [Member]
Dividends from banking securities	1,220	1,720	620
Dividends from other subsidiaries	79	81	278
Interest and other income from subsidiaries	67	79	107
Other income	14	1	8
Total income	1,380	1,881	1,013
Interest expense	219	239	334
Other expenses	50	52	34
Total expense	269	291	368
Income (loss) before income taxes	1,111	1,590	645
Income tax benefit	2	20	26
Income before equity in undistributed earnings of subsidiaries	1,113	1,610	671
Equity in undistributed earnings of subsidiaries in excess of dividends from subsidiaries	616	418	661
Net income	1,729	2,028	1,332
Noncontrolling interests	50	49	43
Dividends on preferred stock	117	63	0
Net income available to common shareholders	$ 1,562	$ 1,916	$ 1,289