XML 79 R60.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Allowance for Loan Losses, by class of loan (Details) (USD $) | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | $ 11,805,986 us-gaap_LoansAndLeasesReceivableAllowance | $ 12,736,921 us-gaap_LoansAndLeasesReceivableAllowance | $ 15,649,594 us-gaap_LoansAndLeasesReceivableAllowance
Charge-Offs | (5,104,491)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs | (6,227,716)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs | (10,454,175)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs
Recoveries | 792,821 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery | 811,781 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery | 756,735 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery
Provision | 1,308,000 us-gaap_ProvisionForLoanAndLeaseLosses | 4,485,000 us-gaap_ProvisionForLoanAndLeaseLosses | 6,784,767 us-gaap_ProvisionForLoanAndLeaseLosses
Ending Balance | 8,802,316 us-gaap_LoansAndLeasesReceivableAllowance | 11,805,986 us-gaap_LoansAndLeasesReceivableAllowance | 12,736,921 us-gaap_LoansAndLeasesReceivableAllowance
Loan balance for reviewing high risk loans minimum | 250,000 cban_LoanBalanceForReviewingHighRiskLoansMinimum | 250,000 cban_LoanBalanceForReviewingHighRiskLoansMinimum | 50,000 cban_LoanBalanceForReviewingHighRiskLoansMinimum
Financing receivable transfer from individual impairment review to collective impairment review |  | 4,100,000 cban_FinancingReceivableTransferFromIndividualImpairmentReviewToCollectiveImpairmentReview |
Impaired loans below the $250,000 review threshold | 3,885,411 cban_ImpairedFinancingReceivableRecordedInvestmentBelowReviewThreshold | 2,821,199 cban_ImpairedFinancingReceivableRecordedInvestmentBelowReviewThreshold |
Amount of impaired loans below old individual impairment review level of $50,000 |  |  | 1,026,624 cban_AmountOfImpairedLoansBelowOldIndividualImpairmentReviewLevel
Substandard [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Substandard loans, not classified as impaired | 9,356,253 cban_SubstandardLoansNotClassifiedAsImpaired / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 6,664,935 cban_SubstandardLoansNotClassifiedAsImpaired / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember |
Specific allocation associated with Substandard loans | 747,982 cban_SpecificAllocationAssociatedWithSubstandardLoans / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember | 260,742 cban_SpecificAllocationAssociatedWithSubstandardLoans / us-gaap_InternalCreditAssessmentAxis = us-gaap_SubstandardMember |
Commercial [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 1,017,073 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 981,021 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 1,070,560 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember
Charge-Offs | (624,944)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | (120,690)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | (653,389)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember
Recoveries | 76,002 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 55,829 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 139,802 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember
Provision | 29,430 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 100,913 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 424,048 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember
Ending Balance | 497,561 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 1,017,073 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 981,021 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember
Agricultural [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 293,886 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | 296,175 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | 297,168 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember
Charge-Offs | 0 us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | (34,502)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | (3,028)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember
Recoveries | 2,700 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | 6,200 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | 0 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember
Provision | 7,586 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | 26,013 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | 2,035 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember
Ending Balance | 304,172 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | 293,886 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember | 296,175 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_AgriculturalMember
Commercial Construction [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 1,782,179 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 1,890,200 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 3,122,594 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Charge-Offs | (1,543,099)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | (2,071,162)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | (4,106,124)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Recoveries | 485,005 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 253,459 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 209,352 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Provision | 498,610 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 1,709,682 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 2,664,378 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Ending Balance | 1,222,695 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 1,782,179 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember | 1,890,200 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstateConstructionFinancingReceivableMember
Residential Construction [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 138,092 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 138,092 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 138,092 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember
Charge-Offs | 0 us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 0 us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 0 us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember
Recoveries | 0 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 0 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 0 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember
Provision | 0 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 0 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 0 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember
Ending Balance | 138,092 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 138,092 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember | 138,092 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_ResidentialConstructionMember
Commercial Real Estate [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 4,379,276 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 5,162,839 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 6,448,064 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Charge-Offs | (1,326,825)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | (2,872,408)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | (4,325,642)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Recoveries | 90,042 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 297,984 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 232,880 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Provision | 522,284 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 1,790,861 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 2,807,537 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Ending Balance | 3,664,777 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 4,379,276 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember | 5,162,839 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialRealEstatePortfolioSegmentMember
Residential [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 3,278,269 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 3,405,947 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 3,695,357 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Charge-Offs | (1,033,966)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | (706,242)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | (960,620)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Recoveries | 31,127 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 64,583 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 47,690 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Provision | 149,897 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 513,981 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 623,520 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Ending Balance | 2,425,327 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 3,278,269 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember | 3,405,947 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Farmland [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 311,494 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | 290,526 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | 364,663 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember
Charge-Offs | (233,580)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | (20,977)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | (224,725)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember
Recoveries | 20,000 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | 21,762 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | 4,716 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember
Provision | 5,886 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | 20,183 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | 145,872 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember
Ending Balance | 103,800 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | 311,494 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember | 290,526 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = cban_FarmlandMember
Consumer [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 243,253 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | 227,774 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | 205,154 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Charge-Offs | (342,077)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | (397,822)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | (169,249)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Recoveries | 72,477 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | 93,520 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | 81,956 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Provision | 93,261 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | 319,781 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | 109,913 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Ending Balance | 66,914 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | 243,253 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember | 227,774 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ConsumerPortfolioSegmentMember
Other [Member] |  |  |
Activity in allowance for loan losses, segregated by class of loan [Roll Forward] |  |  |
Beginning Balance | 362,464 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 344,347 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 307,942 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Charge-Offs | 0 us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | (3,913)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | (11,398)us-gaap_AllowanceForLoanAndLeaseLossesWriteOffs / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Recoveries | 15,468 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 18,444 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 40,339 us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Provision | 1,046 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 3,586 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | 7,464 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember
Ending Balance | $ 378,978 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | $ 362,464 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember | $ 344,347 us-gaap_LoansAndLeasesReceivableAllowance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_UnallocatedFinancingReceivablesMember

X
- Definition Amount of impaired loans below old individual impairment review level. + References No definition available. + Details
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- Definition The effect of a change in method of evaluating loans for individual impairment review. + References No definition available. + Details
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- Definition Amount of investment of impaired financing receivables below the $250,000 threshold for review and were not individually reviewed for impairment. + References No definition available. + Details
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- Definition Minimum loan balance for reviewing. + References No definition available. + Details
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- Definition A category of financing receivables that are inadequately protected by the current sound worth and paying capacity of the obligor or of the collateral pledged, if any. Loans so classified have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They are characterized by the distinct possibility that the creditor will sustain some loss if the deficiencies are not corrected. + References No definition available. + Details
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- Definition A category of financing receivables that are inadequately protected by the current sound worth and paying capacity of the obligor or of the collateral pledged, if any. Loans so classified have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They are characterized by the distinct possibility that the creditor will sustain some loss if the deficiencies are not corrected. + References No definition available. + Details
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- Definition Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss. + References Reference 1: 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(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
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- Definition Amount of recovery of financing receivables doubtful of collection that were previously charged off. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
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- Details
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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: 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(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Subparagraph d -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section L -Subsection 1 + Details
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- Definition Amount of expense related to estimated loss from loan and lease transactions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524 + Details
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