Fair Value (Schedule Of Fair Value Measurements Using Significant Unobservable Inputs) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Other Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Liabilities
Transfers in to Level 3, Liabilities
Transfers out of Level 3, Liabilities
Included in Revenue, Liabilities
Included in Other Comprehensive Income, Liabilities
Purchases, Liabilities
Issuances, Liabilities	20
Sales, Liabilities
Settlements, Liabilities
Fair Value, ending balance, Liabilities	20
Change in Unrealized Gains (Losses) Related to Financial Instruments
Assets Carried At Fair Value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	5,761	7,556
Transfers in to Level 3, Assets	115
Transfers out of Level 3, Assets	(4,590)
Included in Revenue, Assets	437	86
Included in Other Comprehensive Income, Assets	(22)	271
Purchases, Assets	8,212
Issuances, Assets
Sales, Assets	(59)
Settlements, Assets	(1,163)
Purchases, Issuances and Settlements, Net, Assets		1,633
Transfers Into and/or Out of Level 3, Assets		(3,785)
Fair Value, ending balance, Assets	8,691	5,761
Change in Unrealized Gains (Losses) Related to Financial Instruments	(59)	(41)
Liabilities Carried At Fair Value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Liabilities	269	147
Transfers in to Level 3, Liabilities
Transfers out of Level 3, Liabilities
Included in Revenue, Liabilities	(111)
Included in Other Comprehensive Income, Liabilities
Purchases, Liabilities	(7)
Issuances, Liabilities	253	(72)
Sales, Liabilities	(7)
Settlements, Liabilities	(196)
Purchases, Issuances and Settlements, Net, Liabilities		194
Transfers Into and/or Out of Level 3, Liabilities
Fair Value, ending balance, Liabilities	201	269
Change in Unrealized Gains (Losses) Related to Financial Instruments	(50)	(36)
Other [Member] | Accrued Expenses And Other Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Liabilities	9	9
Transfers in to Level 3, Liabilities
Transfers out of Level 3, Liabilities
Included in Revenue, Liabilities
Included in Other Comprehensive Income, Liabilities
Purchases, Liabilities
Issuances, Liabilities
Sales, Liabilities
Settlements, Liabilities
Purchases, Issuances and Settlements, Net, Liabilities
Transfers Into and/or Out of Level 3, Liabilities
Fair Value, ending balance, Liabilities	9	9
Change in Unrealized Gains (Losses) Related to Financial Instruments
State And Political Subdivisions [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	50	2
Transfers in to Level 3, Assets	1
Transfers out of Level 3, Assets	(3)
Included in Revenue, Assets
Included in Other Comprehensive Income, Assets
Purchases, Assets	2
Issuances, Assets
Sales, Assets
Settlements, Assets
Purchases, Issuances and Settlements, Net, Assets		(1)
Transfers Into and/or Out of Level 3, Assets		49
Fair Value, ending balance, Assets	50	50
Change in Unrealized Gains (Losses) Related to Financial Instruments
Collateralized Mortgage Obligations [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	359	199
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets	(519)
Included in Revenue, Assets	522	(35)
Included in Other Comprehensive Income, Assets	(4)	6
Purchases, Assets	428
Issuances, Assets
Sales, Assets
Settlements, Assets	(559)
Purchases, Issuances and Settlements, Net, Assets		362
Transfers Into and/or Out of Level 3, Assets		(173)
Fair Value, ending balance, Assets	227	359
Change in Unrealized Gains (Losses) Related to Financial Instruments
Other U.S. Debt Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	3	3
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets
Included in Revenue, Assets
Included in Other Comprehensive Income, Assets
Purchases, Assets
Issuances, Assets
Sales, Assets
Settlements, Assets	(1)
Purchases, Issuances and Settlements, Net, Assets
Transfers Into and/or Out of Level 3, Assets
Fair Value, ending balance, Assets	2	3
Change in Unrealized Gains (Losses) Related to Financial Instruments
Investment Securities Available For Sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	5,507	7,428
Transfers in to Level 3, Assets	115
Transfers out of Level 3, Assets	(4,590)
Included in Revenue, Assets	561	141
Included in Other Comprehensive Income, Assets	(22)	271
Purchases, Assets	7,969
Issuances, Assets
Sales, Assets	(52)
Settlements, Assets	(975)
Purchases, Issuances and Settlements, Net, Assets		1,452
Transfers Into and/or Out of Level 3, Assets		(3,785)
Fair Value, ending balance, Assets	8,513	5,507
Change in Unrealized Gains (Losses) Related to Financial Instruments
Foreign Exchange Contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	254	128
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets
Included in Revenue, Assets	(134)	(55)
Included in Other Comprehensive Income, Assets
Purchases, Assets	236
Issuances, Assets
Sales, Assets
Settlements, Assets	(188)
Purchases, Issuances and Settlements, Net, Assets		181
Transfers Into and/or Out of Level 3, Assets
Fair Value, ending balance, Assets	168	254
Change in Unrealized Gains (Losses) Related to Financial Instruments	(68)	(41)
Foreign Exchange Contracts [Member] | Accrued Expenses And Other Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Liabilities	260	138
Transfers in to Level 3, Liabilities
Transfers out of Level 3, Liabilities
Included in Revenue, Liabilities	(122)
Included in Other Comprehensive Income, Liabilities
Purchases, Liabilities
Issuances, Liabilities	219	(72)
Sales, Liabilities
Settlements, Liabilities	(196)
Purchases, Issuances and Settlements, Net, Liabilities		194
Transfers Into and/or Out of Level 3, Liabilities
Fair Value, ending balance, Liabilities	161	260
Change in Unrealized Gains (Losses) Related to Financial Instruments	(60)	(36)
Interest-Rate Contracts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets
Included in Revenue, Assets	10
Included in Other Comprehensive Income, Assets
Purchases, Assets	7
Issuances, Assets
Sales, Assets	(7)
Settlements, Assets
Fair Value, ending balance, Assets	10
Change in Unrealized Gains (Losses) Related to Financial Instruments	9
Interest-Rate Contracts [Member] | Accrued Expenses And Other Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Liabilities
Transfers in to Level 3, Liabilities
Transfers out of Level 3, Liabilities
Included in Revenue, Liabilities	11
Included in Other Comprehensive Income, Liabilities
Purchases, Liabilities	(7)
Issuances, Liabilities	14
Sales, Liabilities	(7)
Settlements, Liabilities
Fair Value, ending balance, Liabilities	11
Change in Unrealized Gains (Losses) Related to Financial Instruments	10
Derivative Instruments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	254
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets
Included in Revenue, Assets	(124)
Included in Other Comprehensive Income, Assets
Purchases, Assets	243
Issuances, Assets
Sales, Assets	(7)
Settlements, Assets	(188)
Fair Value, ending balance, Assets	178
Change in Unrealized Gains (Losses) Related to Financial Instruments	(59)
Derivative Instruments [Member] | Accrued Expenses And Other Liabilities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Liabilities	269	147
Transfers in to Level 3, Liabilities
Transfers out of Level 3, Liabilities
Included in Revenue, Liabilities	(111)
Included in Other Comprehensive Income, Liabilities
Purchases, Liabilities	(7)
Issuances, Liabilities	233	(72)
Sales, Liabilities	(7)
Settlements, Liabilities	(196)
Purchases, Issuances and Settlements, Net, Liabilities		194
Transfers Into and/or Out of Level 3, Liabilities
Fair Value, ending balance, Liabilities	181	269
Change in Unrealized Gains (Losses) Related to Financial Instruments	(50)	(36)
U.S. Treasury And Federal Agencies [Member] | Direct Obligations [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets	(40)
Included in Revenue, Assets
Included in Other Comprehensive Income, Assets
Purchases, Assets	40
Issuances, Assets
Sales, Assets
Settlements, Assets
Fair Value, ending balance, Assets
Change in Unrealized Gains (Losses) Related to Financial Instruments
U.S. Treasury And Federal Agencies [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	673	58
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets	(936)
Included in Revenue, Assets		(1)
Included in Other Comprehensive Income, Assets	1	(1)
Purchases, Assets	1,540
Issuances, Assets
Sales, Assets
Settlements, Assets	(89)
Purchases, Issuances and Settlements, Net, Assets		659
Transfers Into and/or Out of Level 3, Assets		(42)
Fair Value, ending balance, Assets	1,189	673
Change in Unrealized Gains (Losses) Related to Financial Instruments
Asset-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	3,277	5,997
Transfers in to Level 3, Assets	114
Transfers out of Level 3, Assets	(1,315)
Included in Revenue, Assets	38	119
Included in Other Comprehensive Income, Assets	(17)	225
Purchases, Assets	1,795
Issuances, Assets
Sales, Assets	(49)
Settlements, Assets	(94)
Purchases, Issuances and Settlements, Net, Assets		(792)
Transfers Into and/or Out of Level 3, Assets		(2,272)
Fair Value, ending balance, Assets	3,749	3,277
Change in Unrealized Gains (Losses) Related to Financial Instruments
Asset-Backed Securities [Member] | Student Loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	1,234	3,175
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets	(785)
Included in Revenue, Assets	3	9
Included in Other Comprehensive Income, Assets	(21)	81
Purchases, Assets	421
Issuances, Assets
Sales, Assets
Settlements, Assets	8
Purchases, Issuances and Settlements, Net, Assets		(317)
Transfers Into and/or Out of Level 3, Assets		(1,714)
Fair Value, ending balance, Assets	860	1,234
Change in Unrealized Gains (Losses) Related to Financial Instruments
Asset-Backed Securities [Member] | Credit Cards [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	43	312
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets	(285)
Included in Revenue, Assets	4	17
Included in Other Comprehensive Income, Assets	(2)	(16)
Purchases, Assets	301
Issuances, Assets
Sales, Assets
Settlements, Assets	30
Purchases, Issuances and Settlements, Net, Assets		(31)
Transfers Into and/or Out of Level 3, Assets		(239)
Fair Value, ending balance, Assets	91	43
Change in Unrealized Gains (Losses) Related to Financial Instruments
Asset-Backed Securities [Member] | Sub-Prime [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets		3
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets
Included in Revenue, Assets		1
Included in Other Comprehensive Income, Assets
Purchases, Assets
Issuances, Assets
Sales, Assets
Settlements, Assets
Purchases, Issuances and Settlements, Net, Assets
Transfers Into and/or Out of Level 3, Assets		(4)
Fair Value, ending balance, Assets
Change in Unrealized Gains (Losses) Related to Financial Instruments
Asset-Backed Securities [Member] | Other Asset-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	2,000	2,507
Transfers in to Level 3, Assets	114
Transfers out of Level 3, Assets	(245)
Included in Revenue, Assets	31	92
Included in Other Comprehensive Income, Assets	6	160
Purchases, Assets	1,073
Issuances, Assets
Sales, Assets	(49)
Settlements, Assets	(132)
Purchases, Issuances and Settlements, Net, Assets		(444)
Transfers Into and/or Out of Level 3, Assets		(315)
Fair Value, ending balance, Assets	2,798	2,000
Change in Unrealized Gains (Losses) Related to Financial Instruments
Non-U.S. Debt Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	1,145	1,169
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets	(1,777)
Included in Revenue, Assets	1	58
Included in Other Comprehensive Income, Assets	(2)	41
Purchases, Assets	4,164
Issuances, Assets
Sales, Assets	(3)
Settlements, Assets	(232)
Purchases, Issuances and Settlements, Net, Assets		1,224
Transfers Into and/or Out of Level 3, Assets		(1,347)
Fair Value, ending balance, Assets	3,296	1,145
Change in Unrealized Gains (Losses) Related to Financial Instruments
Non-U.S. Debt Securities [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	396	768
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets	(838)
Included in Revenue, Assets		35
Included in Other Comprehensive Income, Assets	(9)	7
Purchases, Assets	1,920
Issuances, Assets
Sales, Assets
Settlements, Assets	(12)
Purchases, Issuances and Settlements, Net, Assets		576
Transfers Into and/or Out of Level 3, Assets		(990)
Fair Value, ending balance, Assets	1,457	396
Change in Unrealized Gains (Losses) Related to Financial Instruments
Non-U.S. Debt Securities [Member] | Asset-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	740	361
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets	(939)
Included in Revenue, Assets	1	24
Included in Other Comprehensive Income, Assets	7	31
Purchases, Assets	2,179
Issuances, Assets
Sales, Assets	(3)
Settlements, Assets	(217)
Purchases, Issuances and Settlements, Net, Assets		686
Transfers Into and/or Out of Level 3, Assets		(362)
Fair Value, ending balance, Assets	1,768	740
Change in Unrealized Gains (Losses) Related to Financial Instruments
Non-U.S. Debt Securities [Member] | Government Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	1
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets
Included in Revenue, Assets
Included in Other Comprehensive Income, Assets
Purchases, Assets
Issuances, Assets
Sales, Assets
Settlements, Assets	(1)
Purchases, Issuances and Settlements, Net, Assets		1
Transfers Into and/or Out of Level 3, Assets
Fair Value, ending balance, Assets		1
Change in Unrealized Gains (Losses) Related to Financial Instruments
Non-U.S. Debt Securities [Member] | Other [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, beginning balance, Assets	8	40
Transfers in to Level 3, Assets
Transfers out of Level 3, Assets
Included in Revenue, Assets		(1)
Included in Other Comprehensive Income, Assets		3
Purchases, Assets	65
Issuances, Assets
Sales, Assets
Settlements, Assets	(2)
Purchases, Issuances and Settlements, Net, Assets		(39)
Transfers Into and/or Out of Level 3, Assets		5
Fair Value, ending balance, Assets	71	8
Change in Unrealized Gains (Losses) Related to Financial Instruments