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Summary of Significant Accounting Policies (Details) (USD $) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013
Summary of Significant Accounting Policies [Abstract] |  |
Percentage of loan portfolio concentrated in loans secured by real estate (in hundredths) | 87.00%cban_PercentageOfLoanPortfolioConcentratedInLoansSecuredByRealEstate |
Discounted percentage for selling and marketing cost (in hundredths) | 10.00%cban_DiscountedPercentageForSellingAndMarketingCost |
Income Taxes [Abstract] |  |
Probability of uncertain tax positions of being realized upon settlement, minimum (in hundredths) | 50.00%cban_ProbabilityOfUncertainTaxPositionsOfBeingRealizedUponSettlementMinimum |
Bank-Owned Life Insurance [Abstract] |  |
Cash surrender value of insurance contracts | $ 14,530,851 us-gaap_CashSurrenderValueOfLifeInsurance | $ 13,940,176 us-gaap_CashSurrenderValueOfLifeInsurance
Banking Premises [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Methods | Straight-Line and Accelerated |
Banking Premises [Member] | Minimum [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Useful lives of the assets | 15 years |
Banking Premises [Member] | Maximum [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Useful lives of the assets | 40 years |
Furniture and Equipment [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Methods | Straight-Line and Accelerated |
Furniture and Equipment [Member] | Minimum [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Useful lives of the assets | 5 years |
Furniture and Equipment [Member] | Maximum [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Useful lives of the assets | 10 years |

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- Definition Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 17 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 4 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765 + Details
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- Definition Description of the methodology for computing depreciation for classes of depreciable assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 + Details
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