Number of low income housing credit investments.

No definition available.

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- Definition

Revenues of consolidated VIEs recorded in other noninterest income and interest income on loans on the entity's consolidated statements of income.

+ References

No definition available.

+ Details

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- Definition

Other noninterest expenses that are not separately presented in any other noninterest expense category.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.14)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=7880789&loc=d3e5710-111685

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- Definition

The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

+ References

+ Details

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Variable Interest Entities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Variable Interest Entity [Line Items]
Expenses related to consolidated VIEs	$ 108	$ 101	$ 216	$ 200
LIHC investments [Member]
Variable Interest Entity [Line Items]
Carrying amount of assets, consolidated VIEs	292		292
Carrying amount of liabilities, consolidated VIEs	7		7
Number of LIHC investment fund	2		2
Trusts that own and lease railcars [Member]
Variable Interest Entity [Line Items]
Carrying amount of assets, consolidated VIEs	97		97
Consolidated VIEs, expenses [Member]
Variable Interest Entity [Line Items]
Revenue related to consolidated VIEs	6		11
Expenses related to consolidated VIEs	7	8	14	15
Trusts that own and lease renewable energy facilities [Member]
Variable Interest Entity [Line Items]
Carrying amount of assets, consolidated VIEs	$ 156		$ 156