Accounting Policies, Loans (Details)	12 Months Ended
Dec. 31, 2021
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

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.

No definition available.

Name:	ctbi_PastDuePeriodAfterWhichLoansMustBeWellSecuredAndInProcessOfCollectionToContinueAccruingInterest
Namespace Prefix:	ctbi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration