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Loans and Allowance for Credit Losses - Troubled Debt Restructuring is 90 Days or More Past Due (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 Contract | Sep. 30, 2013 Contract | Sep. 30, 2014 Contract | Sep. 30, 2013 Contract
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |  |
Number of Contracts |  |  | 3 | 3
Recorded Investment |  |  | $ 18 | $ 18
Number of Contracts | 1 | 2 |  |
Recorded Investment | 5 | 14 |  |
Residential real estate [Member] |  |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |  |
Number of Contracts |  |  | 3 | 1
Recorded Investment |  |  | 18 | 9
Number of Contracts | 1 | 1 |  |
Recorded Investment | 5 | 9 |  |
Loans to individuals [Member] |  |  |  |
Financing Receivable, Recorded Investment, Past Due [Line Items] |  |  |  |
Number of Contracts |  |  | 0 | 2
Recorded Investment |  |  | 0 | 9
Number of Contracts | 0 | 1 |  |
Recorded Investment | $ 0 | $ 5 |  |

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- Definition Financing Receivable, Modification, Subsequent Default, Recorded Investment + References No definition available. + Details
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- Definition Troubled debt restructuring number of contracts 90 days past due. + References No definition available. + Details
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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953682-111524 + Details
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- Definition Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953682-111524 + Details
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- Details
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