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Nature of Banking Activities and Significant Accounting Policies - Additional Information (Detail) (USD $) | 12 Months Ended
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Dec. 31, 2013 Entity | Dec. 31, 2012 | Dec. 31, 2011
Nature Of Banking Activities And Significant Accounting Policies [Line Items] |  |  |
Number of accounts included by parent company | 6 |  |
Recognition of other than temporary impairment on basis of credit loss description | If there is no credit loss, there is no other-than-temporary impairment. If there is a credit loss, other-than-temporary impairment exists, and the credit loss must be recognized in net income and the remaining portion of impairment must be recognized in other comprehensive income. |  |
Gain (loss) on rate lock commitments | $ 0 |  |
Reclassified TDR value | 1,900,000 | 6,300,000 |
Largest amount of tax benefit realized by taxing authority | 50.00% |  |
Liability for unrecognized tax benefits | 0 | 0 |
Potential common shares that would have a dilutive effect | 0 |  |
Average number of common shares outstanding basic and diluted | 4,901,464 | 3,944,506 | 2,953,344
Advertising cost | 269,000 | 364,000 | 368,000
Minimum [Member] |  |  |
Nature Of Banking Activities And Significant Accounting Policies [Line Items] |  |  |
Period of time between issuance of a loan commitment and closing and sale of the loan | 30 days |  |
Management's policy on evaluation of impairment | 250,000 |  |
Minimum [Member] | Software [Member] |  |  |
Nature Of Banking Activities And Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of depreciation of premises and equipment | 3 years |  |
Minimum [Member] | Premises and Equipment [Member] |  |  |
Nature Of Banking Activities And Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of depreciation of premises and equipment | 3 years |  |
Maximum [Member] |  |  |
Nature Of Banking Activities And Significant Accounting Policies [Line Items] |  |  |
Period of time between issuance of a loan commitment and closing and sale of the loan | 60 days |  |
Accrual status of loan | 90 days |  |
Company not considered value of impairment on individual consumer, residential and small commercial loans | $ 250,000 |  |
Maximum [Member] | Software [Member] |  |  |
Nature Of Banking Activities And Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of depreciation of premises and equipment | 7 years |  |
Maximum [Member] | Premises and Equipment [Member] |  |  |
Nature Of Banking Activities And Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of depreciation of premises and equipment | 40 years |  |

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- Definition Amount of small balance homogeneous impaired loans not separately identified. + References No definition available. + Details
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- Definition Amount of substandard and doubtful loans evaluated as impaired. + References No definition available. + Details
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- Definition Gain loss on rate lock commitments. + References No definition available. + Details
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