Additional derivative financial instruments.

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- Definition

Derivative financial instruments.

+ Details

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- Definition

Increase in net interest income due to interest rate swap agreements.

+ Details

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- Definition

Interest rate swap counterparty collateral postings.

+ Details

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- Definition

Net unrealized pre-tax gains losses related to real estate loans hedged held for sale and origination and sale commitments.

+ Details

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- Definition

Notional amount of foreign currency and other derivative instruments not designated as hedging instruments.

+ Details

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5624258-113959

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44D

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Aggregate notional amount of all interest rate derivatives not designated as hedging instruments. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5580258-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5579245-113959

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Derivative financial instruments (Details Textual) (USD $)	9 Months Ended	12 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2011 Interest rate swap agreements [Member]	Sep. 30, 2010 Interest rate swap agreements [Member]	Sep. 30, 2011 Interest rate swap agreements [Member]	Sep. 30, 2010 Interest rate swap agreements [Member]	Sep. 30, 2011 Interest rate contracts [Member]	Dec. 31, 2010 Interest rate contracts [Member]	Sep. 30, 2011 Credit Risk Derivative [Member]
Derivative financial instruments (Textual) [Abstract]
Increase in net interest income due to Interest Rate Swap agreements			$ 9,000,000	$ 10,000,000	$ 28,000,000	$ 32,000,000
Notional value of interest rate contracts entered into trading purposes							13,600,000,000	12,800,000,000
Aggregate fair value of derivative financial instruments in a net liability position	321,000,000								105,000,000
Fair value of collateral posted for derivative financial instruments	285,000,000								71,000,000
Additional derivative financial instruments (Textual) [Abstract]
Notional value of foreign currency and other option and future contracts entered into trading purposes	1,300,000,000	769,000,000
Net unrealized pre-tax gains related to hedged loans held for sale, commitments to originate loans for sale and commitments to sell loans	10,000,000	17,000,000
Fair value of Additional collateral to be posted for derivative financial instruments	34,000,000
Interest rate swap counterparty collateral postings	$ 78,000,000