Commitments and Contingencies (Details)	6 Months Ended
Jun. 30, 2017 Product
Commitments and Contingencies [Abstract]
Number of deposit add-on products for which certain customer reimbursements are to be made	2

Refers to the number of deposit add-on products for which certain customer reimbursements are to be made.

No definition available.

Name:	ctbi_NumberOfDepositAddOnProductsForWhichCertainCustomerReimbursementsAreToBeMade
Namespace Prefix:	ctbi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration