XML 69 R55.htm IDEA: XBRL DOCUMENT
v3.20.4

Accounting Policies (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) Payment Segment | Dec. 31, 2019 USD ($)
Certificates of Deposits in Other Banks [Abstract] |  |
Maturity period of certificates of deposit in other banks | 18 months |
Investments [Abstract] |  |
Securities held-to-maturity | $ 0 | $ 517
Loans [Abstract] |  |
Past due period after which loans must be well secured and in the process of collection to continue accruing interest | 90 days |
Period of current principal and interest payments for reclassifying nonaccrual loans as accruing loans | 6 months |
Allowance for Credit Losses [Abstract] |  |
Impact of difference in amortized cost basis versus consideration of loan balances on allowance for credit losses | 1 |
Number of delinquent monthly payments before loan charge off | Payment | 5 |
Current value assessment period for past due loans secured against real estate | 90 days |
Threshold period past due for initiation of foreclosure proceedings | 120 days |
Goodwill and Core Deposit Intangible [Abstract] |  |
Goodwill | $ 65,490 | $ 65,490
Segment Reporting [Abstract] |  |
Number of operating segments | Segment | 1 |
Minimum [Member] |  |
Allowance for Credit Losses [Abstract] |  |
Percentage exposure of capital | 5.00% |
Other Real Estate Owned [Abstract] |  |
Typical frequency of periodic reviews | 12 months |
Maximum [Member] |  |
Other Real Estate Owned [Abstract] |  |
Typical frequency of periodic reviews | 18 months |
Frequency of periodic reviews in general | 24 months |
Buildings [Member] | Maximum [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful life | 40 years |
Furniture, Fixtures, and Equipment [Member] | Minimum [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful life | 2 years |
Furniture, Fixtures, and Equipment [Member] | Maximum [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful life | 10 years |
Commercial [Member] |  |
Allowance for Credit Losses [Abstract] |  |
Threshold period past due for individual evaluations | 90 days |
Commercial [Member] | 90+ Days Past Due [Member] | Minimum [Member] |  |
Allowance for Credit Losses [Abstract] |  |
Threshold outstanding loan balance for individual evaluations | $ 1,000 |
Commercial [Member] | Nonaccrual Status [Member] | Minimum [Member] |  |
Allowance for Credit Losses [Abstract] |  |
Threshold outstanding loan balance for individual evaluations | 1,000 |
Threshold amount of outstanding loan balance for specific reserve to be created | 1,000 |
Commercial [Member] | TDR [Member] | Minimum [Member] |  |
Allowance for Credit Losses [Abstract] |  |
Threshold outstanding loan balance for individual evaluations | 1,000 |
Threshold amount of outstanding loan balance for specific reserve to be created | 1,000 |
Commercial [Member] | Criticized [Member] | Minimum [Member] |  |
Allowance for Credit Losses [Abstract] |  |
Threshold outstanding loan balance for individual evaluations | 1,000 |
Threshold amount of outstanding loan balance for specific reserve to be created | $ 1,000 |
Commercial [Member] | Unsecured Commercial Loan [Member] |  |
Allowance for Credit Losses [Abstract] |  |
Charge off threshold for loans considered uncollectible | 90 days |
Consumer [Member] | Closed-End Consumer Loan [Member] |  |
Allowance for Credit Losses [Abstract] |  |
Charge off threshold for loans considered uncollectible | 120 days |

X
- References No definition available. + Details
Name: | ctbi_CertificatesOfDepositsInOtherBanksAbstract
Namespace Prefix: | ctbi_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Refer to current value assessment period for past due loans secured against real estate, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ctbi_CurrentValueAssessmentPeriodForPastDueLoansSecuredAgainstRealEstate
Namespace Prefix: | ctbi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Threshold amount of outstanding loan balance for a specific reserve equal to the difference between book value of the loan and the fair value assigned to the collateral to be created until such time as the loan is foreclosed. + References No definition available. + Details
Name: | ctbi_FinancingReceivablesThresholdOutstandingLoanBalanceForSpecificReserveToBeCreated
Namespace Prefix: | ctbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Percentage of the impact of the difference in amortized cost basis versus consideration of loan balances on the allowance for credit losses. + References No definition available. + Details
Name: | ctbi_LoansAndLeasesReceivableAllowanceForCreditLossesDifferenceInAmortizedCostBasisVersusConsiderationOfLoanBalancesPercentage
Namespace Prefix: | ctbi_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Definition Refers to maturity period of certificates of deposit in other banks, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ctbi_MaturityPeriodOfCertificatesOfDepositInOtherBanks
Namespace Prefix: | ctbi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The maximum number of delinquent payments that a closed-end loan (excluding conventional 1-4 family residential loans and installment and revolving loans secured by real estate) may be delinquent before being charged-off. If a loan is considered uncollectable, it is charged off earlier. + References No definition available. + Details
Name: | ctbi_NumberOfDelinquentMonthlyPaymentsBeforeLoanChargeOff
Namespace Prefix: | ctbi_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned generally, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ctbi_OtherRealEstateOwnedFrequencyOfPeriodicReviews
Namespace Prefix: | ctbi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The typical frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ctbi_OtherRealEstateOwnedTypicalFrequencyOfPeriodReviews
Namespace Prefix: | ctbi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Refers to the past due period after which loans must be well secured and in the process of collection to continue accruing interest, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ctbi_PastDuePeriodAfterWhichLoansMustBeWellSecuredAndInProcessOfCollectionToContinueAccruingInterest
Namespace Prefix: | ctbi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The required percentage exposure of capital included as factors in the allowance for credit losses (ACL) model. + References No definition available. + Details
Name: | ctbi_PercentageExposureOfCapitalIncludedAsFactorsInAllowanceForCreditLossesModel
Namespace Prefix: | ctbi_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period for which principal and interest payments must remain current for reclassifying nonaccrual loans as accruing loans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ctbi_PeriodOfCurrentPrincipalAndInterestPaymentsForReclassifyingNonaccrualLoansAsAccruingLoans
Namespace Prefix: | ctbi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Threshold amount outstanding loan balance for individual evaluations of a loan under internal risk grading system. + References No definition available. + Details
Name: | ctbi_ThresholdOutstandingLoanBalanceForIndividualEvaluations
Namespace Prefix: | ctbi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Threshold period past due for individual evaluation, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ctbi_ThresholdPeriodPastDueForIndividualEvaluations
Namespace Prefix: | ctbi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Threshold period past due for the initiation of foreclosure proceedings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | ctbi_ThresholdPeriodPastDueForInitiationOfForeclosureProceedings
Namespace Prefix: | ctbi_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_AllowanceForCreditLossAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Threshold period for when financing receivable is considered past due to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919253-210447 + Details
Name: | us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(10)(1)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=120320667&loc=SL49117168-202975 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details
Name: | us-gaap_Goodwill
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
Name: | us-gaap_HeldToMaturitySecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_LoansAndLeasesReceivableDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_MarketableSecuritiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599 + Details
Name: | us-gaap_NumberOfOperatingSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_OtherRealEstateAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_SegmentReportingAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_FurnitureAndFixturesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentPerformanceStatusAxis=ctbi_NonaccrualStatusMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentPerformanceStatusAxis=ctbi_TroubledDebtRestructuringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InternalCreditAssessmentAxis=us-gaap_CriticizedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ctbi_UnsecuredCommercialLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ctbi_ClosedEndConsumerLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |