Name:	ctbi_CurrentValueAssessmentPeriodForPastDueLoansSecuredAgainstRealEstate
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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.

No definition available.

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Percentage of the impact of the difference in amortized cost basis versus consideration of loan balances on the allowance for credit losses.

No definition available.

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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.

No definition available.

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The required percentage exposure of capital included as factors in the allowance for credit losses (ACL) model.

No definition available.

Name:	ctbi_PercentageExposureOfCapitalIncludedAsFactorsInAllowanceForCreditLossesModel
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Threshold amount outstanding loan balance for individual evaluations of a loan under internal risk grading system.

No definition available.

Name:	ctbi_ThresholdOutstandingLoanBalanceForIndividualEvaluations
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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.

No definition available.

Name:	ctbi_ThresholdPeriodPastDueForIndividualEvaluations
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Data Type:	xbrli:durationItemType
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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.

No definition available.

Name:	ctbi_ThresholdPeriodPastDueForInitiationOfForeclosureProceedings
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- References

No definition available.

Name:	us-gaap_AllowanceForCreditLossAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447

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