Fair Value Disclosures (Roll Forward of Level 3 Assets and Liabilities) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Mortgage banking income	$ 565	$ 840	$ 436
Trading [Member]
Beginning balance	1	1	11
Interest income	0	0	0
Mortgage banking income	0	0	0
Other noninterest income	0	0	(3)
Included in unrealized net holding gains (losses) in OCI (loss)	0	0	0
Purchases	40	4	7
Issuances	0	0	0
Sales	(41)	(4)	(14)
Settlements	0	0	0
Ending balance	0	1	1
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	0	0	0
States and Political Subdivisions [Member]
Beginning balance			119
Interest income			0
Mortgage banking income			0
Other noninterest income			0
Included in unrealized net holding gains (losses) in OCI (loss)			(9)
Issuances			0
Sales			0
Settlements			(53)
Transfers into Level 3			0
Transfers out of Level 3			(57)
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period			0
Other Securities [Member]
Beginning balance			7
Interest income			0
Mortgage banking income			0
Other noninterest income			0
Included in unrealized net holding gains (losses) in OCI (loss)			(1)
Issuances			0
Sales			0
Settlements			(1)
Transfers out of Level 3			(5)
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period			0
Covered Securities [Member]
Beginning balance	994	984	954
Interest income	37	48	54
Mortgage banking income	0	0	0
Other noninterest income	0	0	0
Included in unrealized net holding gains (losses) in OCI (loss)	(14)	88	24
Purchases	0	0
Issuances	0	0	0
Sales	0	0	0
Settlements	(156)	(126)	(48)
Ending balance	861	994	984
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	37	48	54
Residential MSR [Member]
Beginning balance	627	563	830
Interest income	0	0	0
Mortgage banking income	229	(32)	(341)
Other noninterest income	0	0	0
Included in unrealized net holding gains (losses) in OCI (loss)	0	0	0
Purchases	0	0
Issuances	336	270	225
Sales	0	0	0
Settlements	(145)	(174)	(151)
Ending balance	1,047	627	563
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	229	(32)	(341)
Net Derivatives [Member]
Beginning balance	54	59	(25)
Interest income	0	0	0
Mortgage banking income	21	458	151
Other noninterest income	0	0	0
Included in unrealized net holding gains (losses) in OCI (loss)	0	0	0
Purchases	0	0
Issuances	65	308	110
Sales	0	0	0
Settlements	(151)	(771)	(177)
Ending balance	(11)	54	59
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	(11)	54	59
Private Equity and Similar Investments [Member]
Beginning balance	323	261	266
Interest income	0	0	0
Mortgage banking income	0	0	0
Other noninterest income	33	21	64
Included in unrealized net holding gains (losses) in OCI (loss)	0	0	0
Purchases	58	101	61
Issuances	0	0	0
Sales	(59)	(59)	(112)
Settlements	(64)	(1)	(15)
Transfers into Level 3			1
Transfers out of Level 3			(4)
Ending balance	291	323	261
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	$ 22	$ 12	$ 39