Loans and Loans Held for Sale (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Loans by category
Commercial, financial and agricultural	$ 19,787	$ 19,378	$ 16,440
Commercial real estate:
Commercial mortgage	7,807	8,037	8,806
Construction	1,273	1,312	1,845
Total commercial real estate loans	9,080	9,349	10,651
Commercial lease financing	5,755	6,055	6,207
Total commercial loans	34,622	34,782	33,298
Residential - prime loans:
Real estate - residential mortgage	1,967	1,946	1,803
Home equity loans	9,660	9,764	10,048
Total residential - prime loans	11,627	11,710	11,851
Total consumer loans	14,604	14,793	15,254
Total loans	49,226	49,575	48,552
Loans Held For Sale
Commercial, financial and agricultural	28	19	19
Real estate - construction	15	35	61
Commercial lease financing	30	12	7
Total loans held for sale	511	728	426
Changes in loans held for sale
Balance at beginning of the period	728	479	467
New originations	935	1,235	980
Transfers from held to maturity, net	19	19	32
Loan sales	(1,168)	(932)	(991)
Loan draws (payments), net	(3)	(72)	(62)
Transfers to OREO / valuation adjustments		(1)
Balance at end of the period	511	728	426
Segment, Discontinued Operations [Member]
Residential - prime loans:
Total loans	2,927	3,010	3,239
Loans Held For Sale
Total loans held for sale			14
Changes in loans held for sale
Balance at end of the period			14
Commercial Mortgage Backed Securities [Member]
Loans Held For Sale
Real estate - residential mortgage	362	567	287
Residential Mortgage [Member]
Loans Held For Sale
Real estate - residential mortgage	76	95	52
Other loan [Member]
Residential - prime loans:
Home equity loans	507	535	627
Community Bank [Member]
Residential - prime loans:
Home equity loans	9,153	9,229	9,421
Consumer other	1,212	1,192	1,141
Corporate Banking [Member]
Residential - prime loans:
Consumer other	1,765	1,891	2,262
Corporate Banking [Member] \| Marine loan [Member]
Residential - prime loans:
Consumer other	1,654	1,766	2,112
Corporate Banking [Member] \| Other loan [Member]
Residential - prime loans:
Consumer other	$ 111	$ 125	$ 150

Loans held-for-sale, commercial lease financing.

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Loans held for sale commercial real estate construction.

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No definition available.

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Loans held-for-sale payments.

+ References

No definition available.

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Net transfers from held to maturity.

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No definition available.

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Transfers to Oreo valuation adjustments.

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No definition available.

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- Definition

The total gross amount of commercial loans (money lent to commercial entities rather than consumers) made in the form of direct financing leases where the reporting entity (lessor) only recognizes interest revenue from the lease. It also includes the amount of lease financing arising from involvement with leveraged lease transactions where the Entity is in the position of long-term creditor.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 6

-Subparagraph b(iii)

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

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-Publisher AICPA

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-Publisher FASB

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- Definition

Reflects the sum of the gross carrying amounts of the various categories of unpaid commercial loans and leases receivable, primarily issued to businesses. Includes: (1) commercial and industrial loans, consisting of general purpose loans to entities involved in producing, transporting, or merchandising products sold in the course of commerce; (2) agricultural loans consisting of borrowings used to finance major equipment and machinery purchases and expenses, livestock or crop production (including fisheries), and to supplement working capital needs of an entity engaged in farming operations; (3) mortgage loans secured by a [legal] security interest in real property [commercial building or business real property]; (4) obligation in the form of [promissory] notes, used for the funding of construction projects; (5) interbank and other loans to financial institutions for the purpose of liquidity management on the part of the borrower; (6) draws against credit facilities provided to companies involved in mortgage banking activities (warehousing); (7) amounts lent to businesses engaged in international activities (trade financing); (8) lease financings; and (9) loans to governmental entities.

+ References

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Reflects the sum of the gross carrying amounts of the various categories of loans made to individuals for personal needs, including mortgage, home equity, vehicles, credit card, installment, and lease financing.

+ References

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- Definition

Gross amount under revolving lines of credit outstanding extended to a homeowner and collateralized by the equity in the home. Such lines of credit are generally subordinated to the homeowner's mortgage loan or loans. Loan proceeds are generally unrestricted as to use by the borrower.

+ References

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

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph c(i)

-Subsection I

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

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-Publisher SEC

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-Publisher AICPA

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- Definition

Reflects the gross carrying amount of unpaid loans issued to individuals to acquire or improve land or a building or to provide cash to the borrower, and which are secured by the acquired or improved realty. Loans secured by one to four-family residential property of the borrower are generally referred to as residential mortgage loans. Repayment terms for residential mortgage loans may vary considerably. Such loans may be structured to provide for full amortization of principal, partial amortization with a balloon payment at a specified date, or negative amortization. Interest rates may be fixed or variable. This item excludes subordinated loans such as home equity lines of credit.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

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-Paragraph 40, 41

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- Definition

The gross amount of other loans and leases to individuals not otherwise specified in the existing taxonomy.

+ References

No definition available.

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- Definition

The total gross amount of money lent to individual customers including construction financing, residential mortgage loans, and home equity lines of credit.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 8

-Paragraph 40-43

-IssueDate 2006-05-01

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

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-Paragraph 13

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a, b

-Article 9

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph c(i)

-Subsection I

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- Definition

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.

+ References

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

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-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph e

-Subsection I

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- Definition

Reflects the carrying amount of commercial (money lent to commercial entities rather than consumers) and industrial loans other than for real property, held for sale to other entities.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

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- Definition

Mortgage loans to individuals not classified as held for investment but are held for sale to permanent investors. Permanent investors are enterprises that invest in mortgage loans for their own accounts. Examples of permanent investors are insurance companies, commercial or mutual savings banks, savings and loan associations, pension plans and real estate investment trusts. Mortgage loans exclude mortgage-backed securities which are considered a debt security.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 65

-Paragraph 1, 34

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph h

-Subsection I

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Reflects the gross carrying amount of unpaid loans that had been issued to businesses to construct a facility. Acquisition, development and construction (ADC) loans are generally issued sequentially and the net proceeds of the latest debt is used by the borrower to pay off the preceding loan. A construction loan ( in the form of a promissory note) is generally expected to be paid off with the net proceeds from permanent financing.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 8

-Paragraph 52

-IssueDate 2006-05-01

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

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- Definition

Reflects the sum of the gross carrying amounts of unpaid loans issued to businesses to provide financing for cash needs, financial asset purchases, or farm-related purposes. Includes all loans not included in another category. This category shall include, but not be limited to, loans to real estate investment trusts, mortgage companies, banks, and other financial institutions; loans for carrying securities; and loans for agricultural purposes. Do not include loans secured primarily by developed real estate.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 8

-Paragraph 19-30

-IssueDate 2006-05-01

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph c(iv)

-Subsection I

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph b(iv)

-Subsection I

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a(1)

-Article 9

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Reflects the gross carrying amount of unpaid loans issued to businesses to provide financing on existing land or a building, which, pursuant to terms of the underlying debt instrument, are secured at a minimum but possibly exclusively by that real property. Mortgages represent permanent financing, and are issued to replace previously existing mortgages or pay off acquisition, development and construction loans, or to provide cash to the borrower.

+ References

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph e

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

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-Paragraph 51

-IssueDate 2006-05-01

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Reflects the sum of the gross carrying amounts of unpaid loans issued to businesses to acquire, develop, construct, improve, or refinance land or a building. Includes [but is not limited to] commercial mortgage loans, which are secured by a [legal] security interest in real property [commercial building or business real property] which thereby serves as collateral securing repayment of the loan; and construction financing, which is an obligation generally in the form of a [promissory] note, used for the funding of construction projects.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

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-Paragraph 51, 52, 53

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The aggregate amount of loans receivable that will be sold to other entities. Includes mortgage and all other loans (collectively, loans) not classified as held for investment. Such loans are stated at the lower of cost or market (approximates fair value). Mortgage loans exclude mortgage-backed securities which are considered a debt security (other loan).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 65

-Paragraph 4, 5, 6, 7, 8, 9, 12, 17, 28, 29

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 65

-Paragraph 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph d

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 8

-Subparagraph h

-Subsection I

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Reconcile the changes in loans that will be sold to other entities balances to the amounts presented in the consolidated statement of cash flows. Enter the additions to trade accounts that will be sold to other entities for the period.

+ References

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph d

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- Definition

Reconcile the changes in loans that will be sold to other entities balances to the amounts presented in the consolidated statement of cash flows. Enter the deductions to trade accounts that will be sold to other entities for the period.

+ References

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

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

-Subparagraph d

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