Fair Value (Schedule of Fair Value Measurements Using Significant Unobservable Inputs) (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Direct Obligations [Member]
Transfers into Level 3, Assets
Transfers out of Level 3, Assets
Recorded in Revenue, Assets
Recorded in Other Comprehensive Income, Assets
Purchases, Assets	17		17
Settlements, Assets
Fair Value, ending balance, Assets	17		17
Mortgage-Backed Securities [Member]
Fair Value, beginning balance, Assets	898	225	673	58
Transfers into Level 3, Assets
Transfers out of Level 3, Assets			(404)
Recorded in Revenue, Assets				(1)
Recorded in Other Comprehensive Income, Assets		(2)	1	(2)
Purchases, Assets	62		699
Settlements, Assets	(28)		(37)
Purchases, Issuances and Settlements, Net, Assets		(180)		(12)
Transfers Into and/or Out of Level 3, Assets
Fair Value, ending balance, Assets	932	43	932	43
Student Loans [Member]
Fair Value, beginning balance, Assets	1,265	3,046	1,165	3,111
Transfers into Level 3, Assets
Transfers out of Level 3, Assets	(308)		(315)
Recorded in Revenue, Assets	2	2	3	5
Recorded in Other Comprehensive Income, Assets	(1)	3		71
Purchases, Assets	300		421
Settlements, Assets	(12)		(28)
Purchases, Issuances and Settlements, Net, Assets		(64)		(36)
Transfers Into and/or Out of Level 3, Assets		(758)		(922)
Fair Value, ending balance, Assets	1,246	2,229	1,246	2,229
Credit Cards [Member]
Fair Value, beginning balance, Assets	74	39	43	312
Transfers into Level 3, Assets
Transfers out of Level 3, Assets	(16)		(16)
Recorded in Revenue, Assets	1	1	2	15
Recorded in Other Comprehensive Income, Assets			(2)	(15)
Purchases, Assets	20		51
Settlements, Assets			1
Purchases, Issuances and Settlements, Net, Assets		46		18
Transfers Into and/or Out of Level 3, Assets		5		(239)
Fair Value, ending balance, Assets	79	91	79	91
Sub-Prime [Member]
Fair Value, beginning balance, Assets		3		3
Recorded in Revenue, Assets
Recorded in Other Comprehensive Income, Assets		1		1
Purchases, Issuances and Settlements, Net, Assets
Transfers Into and/or Out of Level 3, Assets
Fair Value, ending balance, Assets		4		4
Other Asset-Backed Securities [Member]
Fair Value, beginning balance, Assets	565	1,105	491	1,134
Transfers into Level 3, Assets	114		114
Transfers out of Level 3, Assets	(20)		(20)
Recorded in Revenue, Assets	3	21	7	39
Recorded in Other Comprehensive Income, Assets		4	10	42
Purchases, Assets	17		115
Settlements, Assets	21		(17)
Purchases, Issuances and Settlements, Net, Assets		(61)		(46)
Transfers Into and/or Out of Level 3, Assets				(100)
Fair Value, ending balance, Assets	700	1,069	700	1,069
Total Asset-Backed Securities [Member]
Fair Value, beginning balance, Assets	1,904	4,193	1,699	4,560
Transfers into Level 3, Assets	114		114
Transfers out of Level 3, Assets	(344)		(351)
Recorded in Revenue, Assets	6	24	12	59
Recorded in Other Comprehensive Income, Assets	(1)	8	8	99
Purchases, Assets	337		587
Settlements, Assets	9		(44)
Purchases, Issuances and Settlements, Net, Assets		(79)		(64)
Transfers Into and/or Out of Level 3, Assets		(753)		(1,261)
Fair Value, ending balance, Assets	2,025	3,393	2,025	3,393
Non-U.S. Debt Securities [Member]
Fair Value, beginning balance, Assets	3,540	2,687	2,723	2,606
Transfers into Level 3, Assets
Transfers out of Level 3, Assets	(680)		(963)
Recorded in Revenue, Assets	5	18	9	75
Recorded in Other Comprehensive Income, Assets	4	10	50	148
Purchases, Assets	1,220		2,361
Settlements, Assets	(100)		(191)
Purchases, Issuances and Settlements, Net, Assets		(54)		(53)
Transfers Into and/or Out of Level 3, Assets		(2)		(117)
Fair Value, ending balance, Assets	3,989	2,659	3,989	2,659
State and Political Subdivisions [Member]
Fair Value, beginning balance, Assets	51		50	2
Transfers into Level 3, Assets
Transfers out of Level 3, Assets
Recorded in Revenue, Assets
Recorded in Other Comprehensive Income, Assets	1		2
Purchases, Assets	2		2
Settlements, Assets
Purchases, Issuances and Settlements, Net, Assets
Transfers Into and/or Out of Level 3, Assets		3		1
Fair Value, ending balance, Assets	54	3	54	3
Collateralized Mortgage Obligations [Member]
Fair Value, beginning balance, Assets	228	195	359	199
Transfers into Level 3, Assets
Transfers out of Level 3, Assets	(196)		(329)
Recorded in Revenue, Assets	199	1	333	(208)
Recorded in Other Comprehensive Income, Assets		(4)	(2)	3
Purchases, Assets	142		165
Settlements, Assets	(200)		(353)
Purchases, Issuances and Settlements, Net, Assets		232		430
Transfers Into and/or Out of Level 3, Assets
Fair Value, ending balance, Assets	173	424	173	424
Other U.S. Debt Securities [Member]
Fair Value, beginning balance, Assets	3	3	3	3
Transfers into Level 3, Assets
Transfers out of Level 3, Assets
Recorded in Revenue, Assets
Recorded in Other Comprehensive Income, Assets
Purchases, Assets
Settlements, Assets	(1)		(1)
Purchases, Issuances and Settlements, Net, Assets
Transfers Into and/or Out of Level 3, Assets
Fair Value, ending balance, Assets	2	3	2	3
Total Investment Securities Available for Sale [Member]
Fair Value, beginning balance, Assets	6,624	7,303	5,507	7,428
Transfers into Level 3, Assets	114		114
Transfers out of Level 3, Assets	(1,220)		(2,047)
Recorded in Revenue, Assets	210	43	354	(75)
Recorded in Other Comprehensive Income, Assets	4	12	59	248
Purchases, Assets	1,780		3,831
Settlements, Assets	(320)		(626)
Purchases, Issuances and Settlements, Net, Assets		(81)		301
Transfers Into and/or Out of Level 3, Assets		(752)		(1,377)
Fair Value, ending balance, Assets	7,192	6,525	7,192	6,525
Loans and Leases [Member]
Fair Value, beginning balance, Assets		916
Recorded in Revenue, Assets
Recorded in Other Comprehensive Income, Assets
Purchases, Issuances and Settlements, Net, Assets
Transfers Into and/or Out of Level 3, Assets		(916)
Fair Value, ending balance, Assets
Other Assets [Member]
Fair Value, beginning balance, Assets	235	209	254	128
Transfers into Level 3, Assets
Transfers out of Level 3, Assets
Recorded in Revenue, Assets	(38)	9	(107)	3
Recorded in Other Comprehensive Income, Assets
Purchases, Assets	96		164
Sales, Assets	(2)		(3)
Settlements, Assets	(82)		(99)
Purchases, Issuances and Settlements, Net, Assets		89		176
Transfers Into and/or Out of Level 3, Assets
Fair Value, ending balance, Assets	209	307	209	307
Change in Unrealized Gains (Losses) Related to Financial Instruments	(30)	26	(51)	3
Total Assets Carried at Fair Value [Member]
Fair Value, beginning balance, Assets	6,859	8,428	5,761	7,556
Transfers into Level 3, Assets	114		114
Transfers out of Level 3, Assets	(1,220)		(2,047)
Recorded in Revenue, Assets	172	52	247	(72)
Recorded in Other Comprehensive Income, Assets	4	12	59	248
Purchases, Assets	1,876		3,995
Sales, Assets	(2)		(3)
Settlements, Assets	(402)		(725)
Purchases, Issuances and Settlements, Net, Assets		8		477
Transfers Into and/or Out of Level 3, Assets		(1,668)		(1,377)
Fair Value, ending balance, Assets	7,401	6,832	7,401	6,832
Change in Unrealized Gains (Losses) Related to Financial Instruments	(30)	26	(51)	3
Other Short-Term Borrowing [Member]
Fair Value, beginning balance, Liabilities		674
Recorded in Other Comprehensive Income, Liabilities
Transfers Into and/or Out of Level 3, Liabilities		(674)
Accrued Expenses and Other Liabilities [Member]
Fair Value, beginning balance, Liabilities	241	212	269	147
Transfers into Level 3, Liabilities
Transfers out of Level 3, Liabilities
Recorded in Revenue, Liabilities	(20)	(15)	(87)	(31)
Recorded in Other Comprehensive Income, Liabilities
Purchases, Liabilities	(2)		(3)
Issuances, Liabilities	14		13
Sales, Liabilities	79		144
Settlements, Liabilities	(84)		(108)
Purchases, Issuances and Settlements, Net, Liabilities		87		168
Transfers Into and/or Out of Level 3, Liabilities
Fair Value, ending balance, Liabilities	228	284	228	284
Change in Unrealized Gains (Losses) Related to Financial Instruments	(3)	3	(35)	(17)
Total Liabilities Carried at Fair Value [Member]
Fair Value, beginning balance, Liabilities	241	886	269	147
Transfers into Level 3, Liabilities
Transfers out of Level 3, Liabilities
Recorded in Revenue, Liabilities	(20)	(15)	(87)	(31)
Recorded in Other Comprehensive Income, Liabilities
Purchases, Liabilities	(2)		(3)
Issuances, Liabilities	14		13
Sales, Liabilities	79		144
Settlements, Liabilities	(84)		(108)
Purchases, Issuances and Settlements, Net, Liabilities		87		168
Transfers Into and/or Out of Level 3, Liabilities		(674)
Fair Value, ending balance, Liabilities	228	284	228	284
Change in Unrealized Gains (Losses) Related to Financial Instruments	$ (3)	$ 3	$ (35)	$ (17)

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Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Transfers out of Level3

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Transfers into liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
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This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 32
-Subparagraph c(1)
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This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

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Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

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Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Transfers into assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

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This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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-Publisher FASB
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Transfers out of assets measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.

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This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

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This element represents total gains or losses for the period (realized and unrealized), arising from liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

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This element represents total gains or losses for the period (realized and unrealized), arising from liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

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Issues that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Purchases that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3).

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Sales that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Settlements that have taken place during the period in relation to liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.

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This element represents [net] transfers in to and out of liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Paragraph 32
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This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

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