Advances from Federal Home Loan Bank (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Advances from Federal Home Loan Bank [Abstract]
Monthly amortizing	$ 1,170,000	$ 1,286,000
Term	60,000,000	0
Total FHLB advances	61,170,000	1,286,000
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Total	1,170,000	1,286,000
Within 1 Year	123,000
2 Years	111,000
3 Years	98,000
4 Years	404,000
5 Years	20,000
After 5 Years	414,000
Federal home loan bank collateralized	17,900,000
FHLB maximum borrowing capacity	483,000,000
Federal home loan bank advances	61,200,000
Federal home loan bank letters of credit used for public fund pledging	109,500,000ctbi_LettersOfCreditProvidedByFHLB
Federal home loan bank advances available	312,300,000
Federal home loan bank, advances interest rate, range from (in hundredths)	0.00%
Federal home loan bank, advances interest rate, range to (in hundredths)	6.42%
Weighted average interest rate (in hundredths)	0.20%	1.84%
Term advances maturity [Abstract]
Total term advances	60,000,000	0
Advance #275, 0.17%, due 1/05/15 [Member]
Advances from Federal Home Loan Bank [Abstract]
Term	60,000,000	0
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Weighted average interest rate (in hundredths)	0.17%
Term advances maturity [Abstract]
Total term advances	60,000,000	0
Advance #279 and #280 , 0.17%, Maturing 02/03/15 [Member]
Advances from Federal Home Loan Bank [Abstract]
Term	80,000,000
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Weighted average interest rate (in hundredths)	0.17%
Term advances maturity [Abstract]
Total term advances	$ 80,000,000

Refers to the federal home loan bank advances on monthly amortizing basis.

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Amount of letters of credit provided by FHLB used for public fund pledging.

+ References

No definition available.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of advances from the Federal Home Loan Bank (FHLB).

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Discloses the lowest interest rate applicable to any of the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(3)(a))

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Discloses the highest interest rate applicable to any of the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Describes the weighted average interest rate applicable to the specific advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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