Fair Value Disclosures (Roll Forward of Level 3 Assets and Liabilities) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Mortgage banking income	$ 117	$ 211	$ 465	$ 609
Trading [Member]
Beginning balance	12	1	1	1
Interest income	1	0	1	0
Mortgage banking income	0	0	0	0
Other noninterest income	0	0	0	0
Total realized and unrealized gains or losses included in other comprehensive income (loss)	0	0	0	0
Purchases	29	3	40	3
Issuances	0	0	0	0
Sales	(23)	0	(23)	0
Settlements	0	0	0	0
Ending balance	19	4	19	4
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	0
Covered Securities [Member]
Beginning balance	953	982	994	984
Interest income	12	13	30	31
Mortgage banking income	0	0	0	0
Other noninterest income	0	0	0	0
Total realized and unrealized gains or losses included in other comprehensive income (loss)	(17)	9	(7)	49
Purchases	0	0	0	0
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(46)	(32)	(115)	(92)
Ending balance	902	972	902	972
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	12	13	30	31
Residential MSR [Member]
Beginning balance	892	578	627	563
Interest income	0	0	0	0
Mortgage banking income	22	(30)	177	(69)
Other noninterest income	0	0	0	0
Total realized and unrealized gains or losses included in other comprehensive income (loss)	0	0	0	0
Purchases	0	0	0	0
Issuances	77	61	269	195
Sales	0	0	0	0
Settlements	(35)	(46)	(117)	(126)
Ending balance	956	563	956	563
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	22	(30)	177	(69)
Net Derivatives [Member]
Beginning balance	(89)	68	54	59
Interest income	0	0	0	0
Mortgage banking income	(91)	124	(26)	309
Other noninterest income	0	0	0	0
Total realized and unrealized gains or losses included in other comprehensive income (loss)	0	0	0	0
Purchases	0	0	0	0
Issuances	31	106	58	244
Sales	0	0	0	0
Settlements	195	(170)	(40)	(484)
Ending balance	46	128	46	128
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	46	128	46	128
Private Equity and Similar Investments [Member]
Beginning balance	269	301	323	261
Interest income	0	0	0	0
Mortgage banking income	0	0	0	0
Other noninterest income	6	6	17	10
Total realized and unrealized gains or losses included in other comprehensive income (loss)	0	0	0	0
Purchases	23	12	53	64
Issuances	0	0	0	0
Sales	(8)	(7)	(97)	(25)
Settlements	(2)	(1)	(8)	1
Ending balance	288	311	288	311
Change in unrealized gains (losses) included in earnings for the period, attributable to assets and liabilities still held at end of period	$ 5	$ 6	$ 13	$ 13