Fair Value of Financial Assets and Liabilities, Fair Value Measurements of Assets Measured on Nonrecurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans		$ 2,703
Minimum [Member]
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
Nonrecurring [Member]
Impaired loan (collateral dependent) [Abstract]
Fair value adjustments on collateral dependent loans expense (recovery)		200
Other real estate owned [Abstract]
Other real estate owned, fair value adjustment	$ 100	7,400
Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans		2,703
Other real estate owned	221	570
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans		0
Other real estate owned	0	0
Significant Other Observable Inputs (Level 2) [Member] \| Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans		0
Other real estate owned	0	0
Significant Unobservable Inputs (Level 3) [Member] \| Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Collateral dependent loans		2,703
Other real estate owned	$ 221	$ 570

No definition available.

Name:	ctbi_AssetsMeasuredOnNonRecurringBasisAbstract
Namespace Prefix:	ctbi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the fair value disclosure of collateral dependent loan receivable as presented on the statement of financial position.

+ References

No definition available.

+ Details

Name:	ctbi_CollateralDependentLoansFairValueDisclosure
Namespace Prefix:	ctbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount at which an asset could be bought or sold in a current transaction between willing parties, that is, other than in a forced or liquidation sale.

+ References

No definition available.

+ Details

Name:	ctbi_FairValueAdjustmentOnCollateralDependentLoans
Namespace Prefix:	ctbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount at which an asset could be bought or sold in a current transaction between willing parties, that is, other than in a forced or liquidation sale.

+ References

No definition available.

+ Details

Name:	ctbi_FairValueAdjustmentOnOtherRealEstateOwned
Namespace Prefix:	ctbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

Name:	ctbi_ImpairedLoanCollateralDependentAbstract
Namespace Prefix:	ctbi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents other real estate owned at fair value.

+ References

No definition available.

+ Details

Name:	ctbi_OtherRealEstateOwnedFairValueDisclosure
Namespace Prefix:	ctbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

- 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

- References

No definition available.

+ Details

Name:	us-gaap_OtherRealEstateAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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Data Type:	na
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- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix:
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- Details

Name:	us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
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- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
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- Details

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- Details

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