XML 20 R50.htm IDEA: XBRL DOCUMENT v2.4.1.9
Fair Value of Financial Instruments and Fair Value Measurements, Quantitative Information (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended 12 Months Ended
Mar. 31, 2015
Dec. 31, 2014
Real Estate [Member] | Commercial Construction [Member] | Nonrecurring [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Assets measured at fair value 85us-gaap_AssetsFairValueDisclosure
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Unobservable Inputs [Abstract]    
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Unobservable Inputs [Abstract]    
Adjustment for Differences Between the Comparable Sales (in hundredths) 20.10%us-gaap_FairValueInputsComparabilityAdjustments
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Unobservable Inputs [Abstract]    
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Unobservable Inputs [Abstract]    
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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
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 252.50%us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 75.00%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 50.00%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= 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
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 122.10%us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 42.50%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 30.00%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= cban_FarmlandMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Real Estate [Member] | Income Approach [Member] | Residential Real Estate [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Capitalization Rate (in hundredths) 12.50%cban_FairValueInputsCapitalizationRate
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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= us-gaap_ResidentialPortfolioSegmentMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember		 13.75%cban_FairValueInputsCapitalizationRate
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_ResidentialPortfolioSegmentMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= 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
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstateMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember		 11.00%cban_FairValueInputsCapitalizationRate
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_RealEstateMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
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/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember
Other Real Estate Owned [Member] | Nonrecurring [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Assets measured at fair value 5,985us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember		 6,128us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ 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) (55.00%)us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 (40.00%)us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ 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
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 0.33%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ 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		 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
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 69.36%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 69.36%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= 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) (5.00%)us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 2.50%us-gaap_FairValueInputsComparabilityAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Management Adjustments for Age of Appraisals and/or Current Market Conditions (in hundredths) 29.58%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember		 31.88%cban_FairValueInputsComparabilityManagementAdjustments
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= cban_SalesComparisonApproachValuationTechniqueMember
Other Real Estate Owned [Member] | Income Approach [Member] | Nonrecurring [Member] | Weighted Average [Member]    
Unobservable Inputs [Abstract]    
Capitalization Rate (in hundredths) 10.00%cban_FairValueInputsCapitalizationRate
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember		 10.00%cban_FairValueInputsCapitalizationRate
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember
Discount Rate (in hundredths) 9.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
/ us-gaap_ValuationTechniqueAxis
= us-gaap_IncomeApproachValuationTechniqueMember		 9.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_FairValueByAssetClassAxis
= cban_OtherRealEstateOwnedMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsNonrecurringMember
/ 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 947us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByAssetClassAxis
= cban_StateCountyAndMunicipalMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
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