Credit Quality And Allowance For Credit Losses (Loans By Credit Quality Indicator) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 48,593		$ 45,470
Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	46,700	[1]	43,210	[1]
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	831	[2]	860	[2]
Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	789	[3]	1,050	[3]
Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	273	[4]	350	[4]
Real estate construction
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,955		1,762
Real estate construction | Commercial Real Estate business line
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,606	[5]	1,447	[5]
Real estate construction | Other business lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	349	[6]	315	[6]
Commercial mortgage
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,604		8,787
Commercial mortgage | Commercial Real Estate business line
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,790	[5]	1,678	[5]
Commercial mortgage | Other business lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	6,814	[6]	7,109	[6]
Business loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	44,380		41,536
Business loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	42,572	[1]	39,392	[1]
Business loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	826	[2]	850	[2]
Business loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	776	[3]	1,032	[3]
Business loans | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	206	[4]	262	[4]
Business loans | Commercial
Financing Receivable, Recorded Investment [Line Items]
Total loans	31,520		28,815
Business loans | Commercial | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	30,310	[1]	27,470	[1]
Business loans | Commercial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	560	[2]	590	[2]
Business loans | Commercial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	541	[3]	674	[3]
Business loans | Commercial | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	109	[4]	81	[4]
Business loans | Real estate construction
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,955		1,762
Business loans | Real estate construction | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,930	[1]	1,713	[1]
Business loans | Real estate construction | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	18	[2]	13	[2]
Business loans | Real estate construction | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	5	[3]	15	[3]
Business loans | Real estate construction | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	2	[4]	21	[4]
Business loans | Real estate construction | Commercial Real Estate business line
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,606	[5]	1,447	[5]
Business loans | Real estate construction | Commercial Real Estate business line | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,594	[1],[5]	1,399	[1],[5]
Business loans | Real estate construction | Commercial Real Estate business line | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	11	[2],[5]	13	[2],[5]
Business loans | Real estate construction | Commercial Real Estate business line | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	[3],[5]	15	[3],[5]
Business loans | Real estate construction | Commercial Real Estate business line | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	1	[4],[5]	20	[4],[5]
Business loans | Real estate construction | Other business lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	349	[6]	315	[6]
Business loans | Real estate construction | Other business lines | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	336	[1],[6]	314	[1],[6]
Business loans | Real estate construction | Other business lines | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	7	[2],[6]	0	[2],[6]
Business loans | Real estate construction | Other business lines | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	5	[3],[6]	0	[3],[6]
Business loans | Real estate construction | Other business lines | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	1	[4],[6]	1	[4],[6]
Business loans | Commercial mortgage
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,604		8,787
Business loans | Commercial mortgage | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,086	[1]	8,070	[1]
Business loans | Commercial mortgage | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	207	[2]	237	[2]
Business loans | Commercial mortgage | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	216	[3]	324	[3]
Business loans | Commercial mortgage | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	95	[4]	156	[4]
Business loans | Commercial mortgage | Commercial Real Estate business line
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,790	[5]	1,678	[5]
Business loans | Commercial mortgage | Commercial Real Estate business line | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,652	[1],[5]	1,474	[1],[5]
Business loans | Commercial mortgage | Commercial Real Estate business line | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	69	[2],[5]	92	[2],[5]
Business loans | Commercial mortgage | Commercial Real Estate business line | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	47	[3],[5]	61	[3],[5]
Business loans | Commercial mortgage | Commercial Real Estate business line | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	22	[4],[5]	51	[4],[5]
Business loans | Commercial mortgage | Other business lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	6,814	[6]	7,109	[6]
Business loans | Commercial mortgage | Other business lines | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	6,434	[1],[6]	6,596	[1],[6]
Business loans | Commercial mortgage | Other business lines | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	138	[2],[6]	145	[2],[6]
Business loans | Commercial mortgage | Other business lines | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	169	[3],[6]	263	[3],[6]
Business loans | Commercial mortgage | Other business lines | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	73	[4],[6]	105	[4],[6]
Business loans | Lease financing
Financing Receivable, Recorded Investment [Line Items]
Total loans	805		845
Business loans | Lease financing | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	778	[1]	841	[1]
Business loans | Lease financing | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	26	[2]	3	[2]
Business loans | Lease financing | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	1	[3]	1	[3]
Business loans | Lease financing | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	[4]	0	[4]
Business loans | International
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,496		1,327
Business loans | International | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,468	[1]	1,298	[1]
Business loans | International | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	15	[2]	7	[2]
Business loans | International | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	13	[3]	18	[3]
Business loans | International | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	[4]	4	[4]
Retail loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,213		3,934
Retail loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,128	[1]	3,818	[1]
Retail loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	5	[2]	10	[2]
Retail loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	13	[3]	18	[3]
Retail loans | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	67	[4]	88	[4]
Retail loans | Residential mortgage
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,831		1,697
Retail loans | Residential mortgage | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,790	[1]	1,635	[1]
Retail loans | Residential mortgage | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	2	[2]	3	[2]
Retail loans | Residential mortgage | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	3	[3]	6	[3]
Retail loans | Residential mortgage | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	36	[4]	53	[4]
Retail loans | Consumer
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,382		2,237
Retail loans | Consumer | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,338	[1]	2,183	[1]
Retail loans | Consumer | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	3	[2]	7	[2]
Retail loans | Consumer | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	10	[3]	12	[3]
Retail loans | Consumer | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	31	[4]	35	[4]
Retail loans | Consumer | Home equity
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,658		1,517
Retail loans | Consumer | Home equity | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,620	[1]	1,475	[1]
Retail loans | Consumer | Home equity | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	[2]	4	[2]
Retail loans | Consumer | Home equity | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	8	[3]	5	[3]
Retail loans | Consumer | Home equity | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	30	[4]	33	[4]
Retail loans | Consumer | Other consumer
Financing Receivable, Recorded Investment [Line Items]
Total loans	724		720
Retail loans | Consumer | Other consumer | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	718	[1]	708	[1]
Retail loans | Consumer | Other consumer | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	3	[2]	3	[2]
Retail loans | Consumer | Other consumer | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	2	[3]	7	[3]
Retail loans | Consumer | Other consumer | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 1	[4]	$ 2	[4]

[1] Includes all loans not included in the categories of special mention, substandard or nonaccrual.

[2] Special mention loans are accruing loans that have potential credit weaknesses that deserve management’s close attention, such as loans to borrowers who may be experiencing financial difficulties that may result in deterioration of repayment prospects from the borrower at some future date. This category is generally consistent with the "special mention" category as defined by regulatory authorities.

[3] Substandard loans are accruing loans that have a well-defined weakness, or weaknesses, such as loans to borrowers who may be experiencing losses from operations or inadequate liquidity of a degree and duration that jeopardizes the orderly repayment of the loan. Substandard loans also are distinguished by the distinct possibility of loss in the future if these weaknesses are not corrected. PCI loans are included in the substandard category. This category is generally consistent with the "substandard" category as defined by regulatory authorities.

[4] Nonaccrual loans are loans for which the accrual of interest has been discontinued. For further information regarding nonaccrual loans, refer to the Nonperforming Assets subheading in Note 1 - Basis of Presentation and Accounting Policies. A significant majority of nonaccrual loans are generally consistent with the "substandard" category and the remainder are generally consistent with the "doubtful" category as defined by regulatory authorities.

[5] Primarily loans to real estate developers.

[6] Primarily loans secured by owner-occupied real estate.