XML 20 R78.htm IDEA: XBRL DOCUMENT v2.4.1.9
Fair Value of Financial Instruments and Fair Value Measurements, Quantitative Information (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Impaired Loans [Member] | Commercial [Member] | Nonrecurring [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
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Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths)   0.00%us-gaap_FairValueInputsComparabilityAdjustments
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/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
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/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 90.00%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstateMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
90.00%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstateMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Real Estate [Member] | Sales Comparison [Member] | Commercial Real Estate [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths) 0.00%us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
(94.80%)us-gaap_FairValueInputsComparabilityAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
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Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) (45.00%)cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
(57.50%)cban_FairValueInputsComparabilityManagementAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
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/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Real Estate [Member] | Sales Comparison [Member] | Farmland [Member] | Nonrecurring [Member] | Minimum [Member]    
Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths) (8.30%)us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
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(55.00%)us-gaap_FairValueInputsComparabilityAdjustments
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Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 10.00%cban_FairValueInputsComparabilityManagementAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
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/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
10.00%cban_FairValueInputsComparabilityManagementAdjustments
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= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
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/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Real Estate [Member] | Sales Comparison [Member] | Farmland [Member] | Nonrecurring [Member] | Maximum [Member]    
Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths) 252.50%us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
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= cban_SalesComparisonApproachValuationTechniqueMember
388.00%us-gaap_FairValueInputsComparabilityAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
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/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 50.00%cban_FairValueInputsComparabilityManagementAdjustments
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= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
35.00%cban_FairValueInputsComparabilityManagementAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
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= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Real Estate [Member] | Sales Comparison [Member] | Farmland [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths) (122.10%)us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
(166.50%)us-gaap_FairValueInputsComparabilityAdjustments
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/ us-gaap_RangeAxis
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= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) (30.00%)cban_FairValueInputsComparabilityManagementAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
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/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
(22.50%)cban_FairValueInputsComparabilityManagementAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Real Estate [Member] | Income Approach [Member] | Commercial Construction [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Capitalization Rate (in hundredths)   8.50%cban_FairValueInputsCapitalizationRate
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
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/ us-gaap_RangeAxis
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/ us-gaap_ValuationTechniqueAxis
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Real Estate [Member] | Income Approach [Member] | Residential Real Estate [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Capitalization Rate (in hundredths) 13.75%cban_FairValueInputsCapitalizationRate
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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= us-gaap_IncomeApproachValuationTechniqueMember
 
Real Estate [Member] | Income Approach [Member] | Commercial Real Estate [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Capitalization Rate (in hundredths) 11.00%cban_FairValueInputsCapitalizationRate
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= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember
11.00%cban_FairValueInputsCapitalizationRate
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_ValuationTechniqueAxis
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Other Real Estate Owned [Member] | Nonrecurring [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Assets measured at fair value 6,128,365us-gaap_AssetsFairValueDisclosure
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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7,019,799us-gaap_AssetsFairValueDisclosure
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
Other Real Estate Owned [Member] | Sales Comparison [Member] | Nonrecurring [Member] | Minimum [Member]    
Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths) (40.00%)us-gaap_FairValueInputsComparabilityAdjustments
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= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
(10.00%)us-gaap_FairValueInputsComparabilityAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 0.33%cban_FairValueInputsComparabilityManagementAdjustments
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= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
0.36%cban_FairValueInputsComparabilityManagementAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Other Real Estate Owned [Member] | Sales Comparison [Member] | Nonrecurring [Member] | Maximum [Member]    
Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths) 45.00%us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
319.10%us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
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= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 69.36%cban_FairValueInputsComparabilityManagementAdjustments
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= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
87.81%cban_FairValueInputsComparabilityManagementAdjustments
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= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
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= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Other Real Estate Owned [Member] | Sales Comparison [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths) (2.50%)us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
(154.55%)us-gaap_FairValueInputsComparabilityAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) (31.88%)cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
(29.99%)cban_FairValueInputsComparabilityManagementAdjustments
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
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= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Other Real Estate Owned [Member] | Income Approach [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Discount Rate (in hundredths) 9.00%us-gaap_FairValueInputsDiscountRate
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= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
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10.00%us-gaap_FairValueInputsDiscountRate
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember
Capitalization Rate (in hundredths) 10.00%cban_FairValueInputsCapitalizationRate
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/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember
 
State, County and Municipal [Member] | Recurring [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Assets measured at fair value 948,390us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByAssetClassAxis
= cban_StateCountyAndMunicipalMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
941,265us-gaap_AssetsFairValueDisclosure
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/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
State, County and Municipal [Member] | Discounted Cash Flow Member] | Recurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Discount Rate (in hundredths)    [1]    [1]
[1] The Company relies on a third-party pricing service to value its municipal securities. The details of the unobservable inputs and other adjustments used by the third-party pricing service were not readily available to the Company.