Investment Securities (Schedule Of Gross Pre-Tax Unrealized Losses On Investment Securities) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	$ 16,627	$ 25,040
Available for sale, Gross Unrealized Losses Less than 12 months	165	206
Available for sale, Fair Value 12 months or longer	18,163	17,849
Available for sale, Gross Unrealized Losses 12 months or longer	1,264	1,446
Available for sale, Fair Value Total	34,790	42,889
Available for sale, Gross Unrealized Losses Total	1,429	1,652
Held to maturity, Fair Value Less than 12 months	270	999
Held to maturity, Gross Unrealized Losses Less than 12 months	8	39
Held to maturity, Fair Value 12 months or longer	1,745	1,850
Held to maturity, Gross Unrealized Losses 12 months or longer	196	264
Held to maturity, Fair Value Total	2,015	2,849
Held to maturity, Gross Unrealized Losses Total	204	303
Asset-backed Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Held to maturity, Fair Value 12 months or longer	12	29
Held to maturity, Gross Unrealized Losses 12 months or longer	1	2
Held to maturity, Fair Value Total	12	29
Held to maturity, Gross Unrealized Losses Total	1	2
Non-US Debt Securities, Mortgage-Backed Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Held to maturity, Fair Value Less than 12 months	114	341
Held to maturity, Gross Unrealized Losses Less than 12 months	2	6
Held to maturity, Fair Value 12 months or longer	1,239	1,382
Held to maturity, Gross Unrealized Losses 12 months or longer	160	218
Held to maturity, Fair Value Total	1,353	1,723
Held to maturity, Gross Unrealized Losses Total	162	224
Non-US Debt Securities, Asset-Backed Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Held to maturity, Fair Value Less than 12 months	0	9
Held to maturity, Gross Unrealized Losses Less than 12 months	0	1
Held to maturity, Fair Value 12 months or longer	79	70
Held to maturity, Gross Unrealized Losses 12 months or longer	3	2
Held to maturity, Fair Value Total	79	79
Held to maturity, Gross Unrealized Losses Total	3	3
Non-US Debt Securities, Other [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Held to maturity, Fair Value Less than 12 months	0	0
Held to maturity, Gross Unrealized Losses Less than 12 months	0	0
Held to maturity, Fair Value 12 months or longer	140	138
Held to maturity, Gross Unrealized Losses 12 months or longer	12	17
Held to maturity, Fair Value Total	140	138
Held to maturity, Gross Unrealized Losses Total	12	17
Non U S Debt Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Held to maturity, Fair Value Less than 12 months	114	350
Held to maturity, Gross Unrealized Losses Less than 12 months	2	7
Held to maturity, Fair Value 12 months or longer	1,458	1,590
Held to maturity, Gross Unrealized Losses 12 months or longer	175	237
Held to maturity, Fair Value Total	1,572	1,940
Held to maturity, Gross Unrealized Losses Total	177	244
Collateralized Mortgage Obligations [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Held to maturity, Fair Value Less than 12 months	156	649
Held to maturity, Gross Unrealized Losses Less than 12 months	6	32
Held to maturity, Fair Value 12 months or longer	275	231
Held to maturity, Gross Unrealized Losses 12 months or longer	20	25
Held to maturity, Fair Value Total	431	880
Held to maturity, Gross Unrealized Losses Total	26	57
US Treasury and Federal Agencies, Direct Obligations [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months		1,373
Available for sale, Gross Unrealized Losses Less than 12 months		1
Available for sale, Fair Value 12 months or longer	131
Available for sale, Gross Unrealized Losses 12 months or longer	1
Available for sale, Fair Value Total	131	1,373
Available for sale, Gross Unrealized Losses Total	1	1
US Treasury and Federal Agencies, Mortgage-backed Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	8,079	4,714
Available for sale, Gross Unrealized Losses Less than 12 months	96	26
Available for sale, Fair Value 12 months or longer	355	370
Available for sale, Gross Unrealized Losses 12 months or longer	2	2
Available for sale, Fair Value Total	8,434	5,084
Available for sale, Gross Unrealized Losses Total	98	28
Asset-backed Securities, Student Loans [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	1,606	2,642
Available for sale, Gross Unrealized Losses Less than 12 months	12	23
Available for sale, Fair Value 12 months or longer	10,874	10,706
Available for sale, Gross Unrealized Losses 12 months or longer	636	688
Available for sale, Fair Value Total	12,480	13,348
Available for sale, Gross Unrealized Losses Total	648	711
Asset-backed Securities, Credit Cards [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	1,685	2,581
Available for sale, Gross Unrealized Losses Less than 12 months	6	6
Available for sale, Fair Value 12 months or longer	311	1,461
Available for sale, Gross Unrealized Losses 12 months or longer	2	8
Available for sale, Fair Value Total	1,996	4,042
Available for sale, Gross Unrealized Losses Total	8	14
Asset-backed Securities, Sub-prime [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	0	16
Available for sale, Gross Unrealized Losses Less than 12 months	0	1
Available for sale, Fair Value 12 months or longer	1,290	1,360
Available for sale, Gross Unrealized Losses 12 months or longer	361	446
Available for sale, Fair Value Total	1,290	1,376
Available for sale, Gross Unrealized Losses Total	361	447
Asset-backed Securities, Other [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	1,031	1,482
Available for sale, Gross Unrealized Losses Less than 12 months	23	19
Available for sale, Fair Value 12 months or longer	1,125	1,122
Available for sale, Gross Unrealized Losses 12 months or longer	77	106
Available for sale, Fair Value Total	2,156	2,604
Available for sale, Gross Unrealized Losses Total	100	125
Asset-backed Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	4,322	6,721
Available for sale, Gross Unrealized Losses Less than 12 months	41	49
Available for sale, Fair Value 12 months or longer	13,600	14,649
Available for sale, Gross Unrealized Losses 12 months or longer	1,076	1,248
Available for sale, Fair Value Total	17,922	21,370
Available for sale, Gross Unrealized Losses Total	1,117	1,297
Non-US Debt Securities, Mortgage-Backed Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	991	6,069
Available for sale, Gross Unrealized Losses Less than 12 months	3	55
Available for sale, Fair Value 12 months or longer	1,777	1,151
Available for sale, Gross Unrealized Losses 12 months or longer	48	52
Available for sale, Fair Value Total	2,768	7,220
Available for sale, Gross Unrealized Losses Total	51	107
Non-US Debt Securities, Asset-Backed Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	827	2,205
Available for sale, Gross Unrealized Losses Less than 12 months	3	14
Available for sale, Fair Value 12 months or longer	335	108
Available for sale, Gross Unrealized Losses 12 months or longer	6	3
Available for sale, Fair Value Total	1,162	2,313
Available for sale, Gross Unrealized Losses Total	9	17
Non-US Debt Securities, Other [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	716	1,543
Available for sale, Gross Unrealized Losses Less than 12 months	2	13
Available for sale, Fair Value 12 months or longer	23	0
Available for sale, Gross Unrealized Losses 12 months or longer	3	0
Available for sale, Fair Value Total	739	1,543
Available for sale, Gross Unrealized Losses Total	5	13
Non-US Equity Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	2,534	9,817
Available for sale, Gross Unrealized Losses Less than 12 months	8	82
Available for sale, Fair Value 12 months or longer	2,135	1,259
Available for sale, Gross Unrealized Losses 12 months or longer	57	55
Available for sale, Fair Value Total	4,669	11,076
Available for sale, Gross Unrealized Losses Total	65	137
State And Political Subdivisions [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	491	171
Available for sale, Gross Unrealized Losses Less than 12 months	4	3
Available for sale, Fair Value 12 months or longer	1,364	1,446
Available for sale, Gross Unrealized Losses 12 months or longer	99	118
Available for sale, Fair Value Total	1,855	1,617
Available for sale, Gross Unrealized Losses Total	103	121
Collateralized Mortgage Obligations [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	892	2,024
Available for sale, Gross Unrealized Losses Less than 12 months	15	43
Available for sale, Fair Value 12 months or longer	547	68
Available for sale, Gross Unrealized Losses 12 months or longer	21	10
Available for sale, Fair Value Total	1,439	2,092
Available for sale, Gross Unrealized Losses Total	36	53
Other U.S. Debt Securities [Member]
Gross Pre-Tax Unrealized Losses On Investment Securities [Line Items]
Available for sale, Fair Value Less than 12 months	309	220
Available for sale, Gross Unrealized Losses Less than 12 months	1	2
Available for sale, Fair Value 12 months or longer	31	57
Available for sale, Gross Unrealized Losses 12 months or longer	8	13
Available for sale, Fair Value Total	340	277
Available for sale, Gross Unrealized Losses Total	$ 9	$ 15