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Derivatives - Credit Value Adjustment Recorded Related to Notional Amount of Derivatives Outstanding (Detail) (USD $) In Thousands, unless otherwise specified | Sep. 30, 2012 | Dec. 31, 2011
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Derivative Instruments [Line Items] |  |
Credit value adjustment | $ (1,836) | $ (2,963)
Interest rate derivatives | 207,822 | 187,368
Risk participation agreements | 86,980 | 128,098
Sold credit protection on risk participation agreements | $ 0 | $ (22,147)

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- Definition Derivatives mark to market adjustment. + References No definition available. + Details
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- Definition Notional amount of risk participation agreement. + References No definition available. + Details
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- Definition Sold credit protection on risk participation agreements. + References No definition available. + Details
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- Definition Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments. + References Reference 1: 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=7476318&loc=SL5579245-113959 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 1B -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959 + Details
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