Accounting Policies, Certificates of Deposit in Other Banks (Details)	12 Months Ended
Dec. 31, 2021
Certificates of Deposits in Other Banks [Abstract]
Maturity period of certificates of deposit in other banks	18 months

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.

No definition available.

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