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Loans - Additional Information (Detail) (USD $) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2014 | Dec. 31, 2013 | Mar. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans held for sale | $ 226,000 | $ 556,000 |
Residential mortgage loan | 22,900,000 | 24,200,000 |
Impaired loans classified as troubled debt restructured | $ 974,000 | $ 861,200 | $ 670,000
Maximum time for re-evaluation (in months) | 12 months |  |
Re-evaluation period for real estate | 2 years |  |
Unsecured consumer loans, credit card credits and overdraft lines of credit reach | 90 days |  |
Delinquent period for charging down consumer loans | 120 days |  |
Delinquent period for charging down commercial and agricultural credits | 120 days |  |
Maximum [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Leverage position of balance sheet | 1.50 |  |
Leverage position of customers | 2.00 |  |
Minimum [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Repayment period of loan with a reasonable reduction of principal balance | 2 years |  |

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- Definition Delinquent Period For Charging Down Consumer Loans + References No definition available. + Details
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- Definition Residential Mortgage Loan + References No definition available. + Details
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- Details
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- Definition Amount of loans held for sale, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph a -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 35 -Paragraph 49 -URI http://asc.fasb.org/extlink&oid=25442802&loc=d3e3084-111518 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section 30 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6490209&loc=d3e48214-111002 + Details
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