Notional Amounts and Fair Values for All Derivative Instruments Included in the Consolidated Balance Sheets (Detail) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Fair value - Derivative Assets	$ 2,111	$ 2,080
Fair value - Derivative Liabilities	1,001	1,043
Accumulated Net Gain (Loss) from Designated or Qualifying Hedges
Derivatives, Fair Value [Line Items]
Fair value - Derivative Assets	399	435
Accumulated Net Gain (Loss) from Designated or Qualifying Hedges \| Fair Value Hedging
Derivatives, Fair Value [Line Items]
Fair value - Derivative Assets	350	399
Accumulated Net Gain (Loss) from Designated or Qualifying Hedges \| Fair Value Hedging \| Interest Rate Swap \| Long-Term Debt
Derivatives, Fair Value [Line Items]
Notional amount	1,705	2,205
Fair value - Derivative Assets	350	399
Accumulated Net Gain (Loss) from Designated or Qualifying Hedges \| Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Fair value - Derivative Assets	49	36
Accumulated Net Gain (Loss) from Designated or Qualifying Hedges \| Cash Flow Hedging \| Interest Rate Swap \| Commercial and Industrial Loans
Derivatives, Fair Value [Line Items]
Notional amount	5,475	3,150
Fair value - Derivative Assets	49	36
Nondesignated
Derivatives, Fair Value [Line Items]
Fair value - Derivative Assets	1,712	1,645
Fair value - Derivative Liabilities	1,001	1,043
Nondesignated \| Risk Management and Other Business Purposes
Derivatives, Fair Value [Line Items]
Fair value - Derivative Assets	704	596
Fair value - Derivative Liabilities	64	55
Nondesignated \| Risk Management and Other Business Purposes \| Interest Rate Contract \| Servicing Rights
Derivatives, Fair Value [Line Items]
Notional amount	7,142	4,487
Fair value - Derivative Assets	197	181
Fair value - Derivative Liabilities	8
Nondesignated \| Risk Management and Other Business Purposes \| Forward Contracts \| Assets Held-for-sale
Derivatives, Fair Value [Line Items]
Notional amount	1,096	999
Fair value - Derivative Assets	7
Fair value - Derivative Liabilities	1	6
Nondesignated \| Risk Management and Other Business Purposes \| Warrant
Derivatives, Fair Value [Line Items]
Notional amount	778	691
Fair value - Derivative Assets	500	415
Nondesignated \| Risk Management and Other Business Purposes \| Swap
Derivatives, Fair Value [Line Items]
Notional amount	1,119	1,092
Fair value - Derivative Liabilities	55	49
Nondesignated \| Customer Accommodation
Derivatives, Fair Value [Line Items]
Fair value - Derivative Assets	1,008	1,049
Fair value - Derivative Liabilities	937	988
Nondesignated \| Customer Accommodation \| Interest Rate Contract
Derivatives, Fair Value [Line Items]
Notional amount	29,100	29,558
Fair value - Derivative Assets	265	272
Fair value - Derivative Liabilities	272	278
Nondesignated \| Customer Accommodation \| Interest Rate Lock Commitments
Derivatives, Fair Value [Line Items]
Notional amount	792	613
Fair value - Derivative Assets	14	12
Fair value - Derivative Liabilities	1
Nondesignated \| Customer Accommodation \| Commodity Contract
Derivatives, Fair Value [Line Items]
Notional amount	3,588	3,558
Fair value - Derivative Assets	234	348
Fair value - Derivative Liabilities	223	338
Nondesignated \| Customer Accommodation \| Foreign Exchange Contract
Derivatives, Fair Value [Line Items]
Notional amount	22,292	16,745
Fair value - Derivative Assets	495	417
Fair value - Derivative Liabilities	$ 441	$ 372

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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