Loans and Allowance for Credit Losses (Details 3) (USD $) In Millions	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2011	Dec. 31, 2010
Additional detail of the allowance for credit losses and related loan balances, by portfolio type
Balance at beginning of year	$ 5,308	$ 5,531
Provision for credit losses	519	1,846
Loans charged off	762	2,511
Less recoveries of loans charged off	(93)	(290)
Net loans charged off	669	2,221
Net change for credit losses to be reimbursed by the FDIC	32	34
Balance at end of year	5,190	5,190
Allowance balance at end of year related to:
Loans individually evaluated for impairment	87	87	93
TDRs collectively evaluated for impairment	794	794	573
Other loans collectively evaluated for impairment	4,176	4,176	4,778
Loans acquired with deteriorated credit quality	133	133	87
Total allowance for credit losses	5,190	5,190
Loan balance at end of year:
Loans individually evaluated for impairment	1,268	1,268	1,096
TDRs collectively evaluated for impairment	4,289	4,289	2,523
Other loans collectively evaluated for impairment	192,901	192,901	187,239
Loans acquired with deteriorated credit quality	6,310	6,310	6,203
Total loans	204,768	204,768	197,061
Commercial loans [Member]
Additional detail of the allowance for credit losses and related loan balances, by portfolio type
Balance at beginning of year	1,109	1,104
Provision for credit losses	15	255
Loans charged off	126	412
Less recoveries of loans charged off	(27)	(78)
Net loans charged off	99	334
Balance at end of year	1,025	1,025
Allowance balance at end of year related to:
Loans individually evaluated for impairment	16	16	38
TDRs collectively evaluated for impairment	37	37
Other loans collectively evaluated for impairment	972	972	1,066
Total allowance for credit losses	1,025	1,025
Loan balance at end of year:
Loans individually evaluated for impairment	177	177	295
TDRs collectively evaluated for impairment	241	241
Other loans collectively evaluated for impairment	53,402	53,402	48,103
Loans acquired with deteriorated credit quality	12	12
Total loans	53,832	53,832	48,398
Commercial real estate loans [Member]
Additional detail of the allowance for credit losses and related loan balances, by portfolio type
Balance at beginning of year	1,258	1,291
Provision for credit losses	88	344
Loans charged off	131	446
Less recoveries of loans charged off	(6)	(32)
Net loans charged off	125	414
Balance at end of year	1,221	1,221
Allowance balance at end of year related to:
Loans individually evaluated for impairment	70	70	55
TDRs collectively evaluated for impairment	17	17
Other loans collectively evaluated for impairment	1,132	1,132	1,235
Loans acquired with deteriorated credit quality	2	2	1
Total allowance for credit losses	1,221	1,221
Loan balance at end of year:
Loans individually evaluated for impairment	903	903	801
TDRs collectively evaluated for impairment	287	287
Other loans collectively evaluated for impairment	34,237	34,237	33,834
Loans acquired with deteriorated credit quality	176	176	60
Total loans	35,603	35,603	34,695
Residential mortgage loans [Member]
Additional detail of the allowance for credit losses and related loan balances, by portfolio type
Balance at beginning of year	841	820
Provision for credit losses	168	437
Loans charged off	124	380
Less recoveries of loans charged off	(2)	(10)
Net loans charged off	122	370
Balance at end of year	887	887
Allowance balance at end of year related to:
Loans individually evaluated for impairment	1	1
TDRs collectively evaluated for impairment	459	459	320
Other loans collectively evaluated for impairment	427	427	500
Total allowance for credit losses	887	887
Loan balance at end of year:
Loans individually evaluated for impairment	6	6
TDRs collectively evaluated for impairment	2,949	2,949	1,957
Other loans collectively evaluated for impairment	32,160	32,160	28,775
Loans acquired with deteriorated credit quality	9	9
Total loans	35,124	35,124	30,732
Credit card portfolio segment [Member]
Additional detail of the allowance for credit losses and related loan balances, by portfolio type
Balance at beginning of year	1,140	1,395
Provision for credit losses	106	314
Loans charged off	203	712
Less recoveries of loans charged off	(25)	(71)
Net loans charged off	178	641
Balance at end of year	1,068	1,068
Allowance balance at end of year related to:
TDRs collectively evaluated for impairment	226	226	223
Other loans collectively evaluated for impairment	842	842	1,172
Total allowance for credit losses	1,068	1,068
Loan balance at end of year:
TDRs collectively evaluated for impairment	580	580	452
Other loans collectively evaluated for impairment	15,752	15,752	16,351
Total loans	16,332	16,332	16,803
Other retail portfolio segment [Member]
Additional detail of the allowance for credit losses and related loan balances, by portfolio type
Balance at beginning of year	843	807
Provision for credit losses	131	477
Loans charged off	175	551
Less recoveries of loans charged off	(33)	(99)
Net loans charged off	142	452
Balance at end of year	832	832
Allowance balance at end of year related to:
TDRs collectively evaluated for impairment	55	55	30
Other loans collectively evaluated for impairment	777	777	777
Total allowance for credit losses	832	832
Loan balance at end of year:
TDRs collectively evaluated for impairment	143	143	114
Other loans collectively evaluated for impairment	48,336	48,336	48,277
Total loans	48,479	48,479	48,391
Total Loans, Excluding Covered Loans [Member]
Additional detail of the allowance for credit losses and related loan balances, by portfolio type
Balance at beginning of year	5,191	5,417
Provision for credit losses	508	1,827
Loans charged off	759	2,501
Less recoveries of loans charged off	(93)	(290)
Net loans charged off	666	2,211
Balance at end of year	5,033	5,033
Allowance balance at end of year related to:
Loans individually evaluated for impairment	87	87	93
TDRs collectively evaluated for impairment	794	794	573
Other loans collectively evaluated for impairment	4,150	4,150	4,750
Loans acquired with deteriorated credit quality	2	2	1
Total allowance for credit losses	5,033	5,033
Loan balance at end of year:
Loans individually evaluated for impairment	1,086	1,086	1,096
TDRs collectively evaluated for impairment	4,200	4,200	2,523
Other loans collectively evaluated for impairment	183,887	183,887	175,340
Loans acquired with deteriorated credit quality	197	197	60
Total loans	189,370	189,370	179,019
Covered portfolio segment [Member]
Additional detail of the allowance for credit losses and related loan balances, by portfolio type
Balance at beginning of year	117	114
Provision for credit losses	11	19
Loans charged off	3	10
Net loans charged off	3	10
Net change for credit losses to be reimbursed by the FDIC	32	34
Balance at end of year	157	157
Allowance balance at end of year related to:
Other loans collectively evaluated for impairment	26	26	28
Loans acquired with deteriorated credit quality	131	131	86
Total allowance for credit losses	157	157
Loan balance at end of year:
Loans individually evaluated for impairment	182	182
TDRs collectively evaluated for impairment	89	89
Other loans collectively evaluated for impairment	9,014	9,014	11,899
Loans acquired with deteriorated credit quality	6,113	6,113	6,143
Total loans	$ 15,398	$ 15,398	$ 18,042

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The balance of financing receivables that were acquired with deteriorated credit quality.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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Reduction to the allowance for credit losses related to collections on financing receivables which have been partially or fully charged off as bad debts.

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Reduction to the allowance for credit losses related to financing receivables deemed uncollectible.

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Reflects the aggregate gross carrying amount of all categories of loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on loans and leases.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5074-111524

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-Publisher AICPA

-Name Statement of Position (SOP)

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-Paragraph 13

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-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

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-Number Title 12

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