Loans and ACL (Aging Analysis of Past Due Loans and Leases) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Total Loans Excluding Government Guaranteed [Member]
Loans and leases, current	$ 116,630	$ 112,638
Loans and leases, 30-89 days past due	1,024	1,112
Loans and leases, 90 days or more past due	1,028	1,232
Nonaccrual loans and leases	841	935
Total loans and leases	119,523	115,917
Commercial and Industrial, Excluding Covered [Member]
Loans and leases, current	39,999	38,110
Loans and leases, 30-89 days past due	21	35
Nonaccrual loans and leases	298	363
Total loans and leases	40,318	38,508
CRE Income Producing Properties, Excluding Covered [Member]
Loans and leases, current	10,347	10,107
Loans and leases, 30-89 days past due	7	8
Nonaccrual loans and leases	84	113
Total loans and leases	10,438	10,228
CRE Construction And Development, Excluding Covered [Member]
Loans and leases, current	2,594	2,329
Loans and leases, 30-89 days past due	2	2
Nonaccrual loans and leases	38	51
Total loans and leases	2,634	2,382
Commercial Other Lending Subsidiaries, Excluding Covered [Member]
Loans and leases, current	4,713	4,482
Loans and leases, 30-89 days past due	11	14
Loans and leases, 90 days or more past due	0	5
Nonaccrual loans and leases	5	1
Total loans and leases	4,729	4,502
Direct Retail Lending, Excluding Covered [Member]
Loans and leases, current	7,696	15,595
Loans and leases, 30-89 days past due	41	132
Loans and leases, 90 days or more past due	11	33
Nonaccrual loans and leases	49	109
Total loans and leases	7,797	15,869
Retail Revolving Credit, Excluding Covered [Member]
Loans and leases, current	2,363	2,370
Loans and leases, 30-89 days past due	20	23
Loans and leases, 90 days or more past due	8	10
Nonaccrual loans and leases	0	0
Total loans and leases	2,391	2,403
Retail Residential Mortgage-Nonguaranteed, Excluding Covered [Member]
Loans and leases, current	30,796	22,747
Loans and leases, 30-89 days past due	513	454
Loans and leases, 90 days or more past due	80	69
Nonaccrual loans and leases	320	243
Total loans and leases	31,709	23,513
Retail Residential Mortgage-Government Guaranteed, Excluding Covered [Member]
Loans and leases, current	324	236
Loans and leases, 30-89 days past due	90	93
Loans and leases, 90 days or more past due	677	806
Total loans and leases	1,091	1,135
Retail Sales Finance, Excluding Covered [Member]
Loans and leases, current	10,348	9,316
Loans and leases, 30-89 days past due	49	56
Loans and leases, 90 days or more past due	3	5
Nonaccrual loans and leases	5	5
Total loans and leases	10,405	9,382
Retail Other Lending Subsidiaries, Excluding Covered [Member]
Loans and leases, current	6,130	5,703
Loans and leases, 30-89 days past due	186	207
Nonaccrual loans and leases	42	50
Total loans and leases	6,358	5,960
Covered [Member]
Loans and leases, current	1,320	1,643
Loans and leases, 30-89 days past due	84	88
Loans and leases, 90 days or more past due	249	304
Nonaccrual loans and leases	0	0
Total loans and leases	$ 1,653	$ 2,035