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Commitments and Off-Balance Sheet Risk - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Dec. 31, 2013 | Dec. 31, 2012
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |
Line of credit facilities | 1 year |
Libor rate period | 30 days |
Fixed rate range of term debt secured by real estate, Maximum | 4.00% |
Fixed rate range of term debt secured by real estate, Maximum | 7.00% |
Term debt secured by real estate balloon payment period | 5 years |
Term debt secured by non real estate collateral maturity period | 5 years |
Remaining amount of fees collected from customers relating to risk participation agreements associated with interest rate swap agreements, reflected as liabilities | $ 0.1 | $ 0.1
Amount of federal reserve requirement | 1.5 | 1.2
Interest rate swap agreement [Member] |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |
Notional amount of the underlying interest rate swap agreements, entered into by commercial loan customers with correspondent banks | 17.9 |
Net fair value of interest rate swaps entered into by commercial loan customer's with correspondent banks | $ (2.3) |
Minimum [Member] |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |
Amortization period for term debt secured by real estate | 10 years |
Interest rates on loans secured by non real estate collateral | 4.00% |
Income recognition period for risk participation agreement fees collected from customers entering into interest rate swap agreements with correspondent banks | 4 years |
Maximum [Member] |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |
Amortization period for term debt secured by real estate | 20 years |
Interest rates on loans secured by non real estate collateral | 7.50% |
Income recognition period for risk participation agreement fees collected from customers entering into interest rate swap agreements with correspondent banks | 15 years |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References 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 + Details
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- Details
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- Definition Income recognition period for risk participation agreement fees collected from customers entering into interest rate swap agreements with correspondent banks. + References No definition available. + Details
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- Definition Interest rates on loans secured by non real estate collateral. + References No definition available. + Details
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- Definition Common variable-rate index used for line of credit facilities commitments secured by accounts receivable and inventory. + References No definition available. + Details
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- Definition Common term for line of credit facilities commitments secured by accounts receivable and inventory. + References No definition available. + Details
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- Definition Remaining amount of fees collected from customers relating to risk participation agreements associated with interest rate swap agreements, reflected as liabilities. + References No definition available. + Details
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- Definition The highest stated interest rate within the mortgage loans included in the loan grouping. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule IV) -URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-29.3) -URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 29 -Article 12 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule IV -Article 5 + Details
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