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Borrowings (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2007
Dec. 31, 2013
Short-term Debt [Line Items]      
Repurchase agreements $ 235,186,000us-gaap_SecuritiesSoldUnderAgreementsToRepurchase   $ 208,067,000us-gaap_SecuritiesSoldUnderAgreementsToRepurchase
Federal funds purchased 11,041,000us-gaap_FederalFundsPurchased   12,465,000us-gaap_FederalFundsPurchased
Total short-term debt 246,227,000us-gaap_ShortTermBorrowings   220,532,000us-gaap_ShortTermBorrowings
Maximum balance for repurchase agreements at any month-end 252,300,000us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount    
Long-term debt [Abstract]      
Junior subordinated debentures, 1.83%, due 6/1/37 61,341,000us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust   61,341,000us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust
Interest rate on junior subordinated debentures (in hundredths)   6.52%us-gaap_DebtInstrumentInterestRateStatedPercentage  
Maturity date of junior subordinated debentures Jun. 01, 2037    
Issuance of capital securities in a private placement   59,500,000us-gaap_ProceedsFromIssuanceOfTrustPreferredSecurities  
Maturity period of debentures   30 years  
Period after which debentures are redeemable   5 years  
Description of variable rate basis three-month LIBOR three-month LIBOR  
Basis spread on variable rate (in hundredths) 1.59%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 1.59%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1  
Subordinated Debentures 9.0% [Member]      
Long-term debt [Abstract]      
Interest rate on junior subordinated debentures (in hundredths) 9.00%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis
= us-gaap_SubordinatedDebenturesSubjectToMandatoryRedemptionMember
   
Subordinated Debentures 8.25% [Member]      
Long-term debt [Abstract]      
Interest rate on junior subordinated debentures (in hundredths) 8.25%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_ScheduleOfSharesSubjectToMandatoryRedemptionBySettlementTermsAxis
= ctbi_SubordinatedDebenturesSubjectToMandatoryRedemptionOneMember
   
Junior Subordinated Debentures [Member]      
Long-term debt [Abstract]      
Junior subordinated debentures, 1.83%, due 6/1/37 61,341,000us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_JuniorSubordinatedDebtMember
  61,341,000us-gaap_JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_JuniorSubordinatedDebtMember
Interest rate on junior subordinated debentures (in hundredths) 1.83%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_LongtermDebtTypeAxis
= us-gaap_JuniorSubordinatedDebtMember
   
Repurchase Agreements [Member]      
Short-term Debt [Line Items]      
Average interest rate (in hundredths) 0.36%us-gaap_DebtWeightedAverageInterestRate
/ us-gaap_ShortTermDebtTypeAxis
= us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember
   
Average balance of repurchase agreements $ 221,200,000us-gaap_ShorttermDebtAverageOutstandingAmount
/ us-gaap_ShortTermDebtTypeAxis
= us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember
   
Federal Funds Purchased [Member]      
Short-term Debt [Line Items]      
Average interest rate (in hundredths) 0.15%us-gaap_DebtWeightedAverageInterestRate
/ us-gaap_ShortTermDebtTypeAxis
= us-gaap_FederalFundsPurchasedMember