No definition available.

Name:	ctbi_AssetsMeasuredOnNonRecurringBasisAbstract
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- Definition

The amount at which an asset could be bought or sold in a current transaction between willing parties, that is, other than in a forced or liquidation sale.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount at which an asset could be bought or sold in a current transaction between willing parties, that is, other than in a forced or liquidation sale.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of realized and unrealized gains and losses recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- References

No definition available.

+ Details

Name:	ctbi_ImpairedLoanCollateralDependentAbstract
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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

+ References

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned generally, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The typical frequency of periodic reviews for appraisals on foreclosed properties and other real estate owned, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 5
-Subparagraph (aa)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(6),(7)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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Fair Market Value of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 631,201	$ 594,936		$ 631,201		$ 594,936
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Total gains (losses)	0		$ (351)	$ (660)	$ (381)
Minimum [Member]
Other real estate owned [Abstract]
Typical frequency of periodic reviews				12 months
Maximum [Member]
Other real estate owned [Abstract]
Typical frequency of periodic reviews				18 months
Frequency of periodic reviews in general				24 months
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	70,125	69,453		$ 70,125		69,453
Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	561,076	525,483		561,076		525,483
Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0		0		0
Recurring [Member] \| Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights	2,964	3,236		2,964		3,236
Recurring [Member] \| Fair Value [Member] \| U.S. Treasury and Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	245,111	239,394		245,111		239,394
Recurring [Member] \| Fair Value [Member] \| State and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	133,175	129,215		133,175		129,215
Recurring [Member] \| Fair Value [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	227,771	201,576		227,771		201,576
Recurring [Member] \| Fair Value [Member] \| CRA Investments Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	25,144	24,751		25,144		24,751
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights	0	0		0		0
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member] \| U.S. Treasury and Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	44,981	44,702		44,981		44,702
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member] \| State and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0		0		0
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0		0		0
Recurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member] \| CRA Investments Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	25,144	24,751		25,144		24,751
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights	0	0		0		0
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member] \| U.S. Treasury and Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	200,130	194,692		200,130		194,692
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member] \| State and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	133,175	129,215		133,175		129,215
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	227,771	201,576		227,771		201,576
Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member] \| CRA Investments Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0		0		0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage servicing rights	2,964	3,236		2,964		3,236
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member] \| U.S. Treasury and Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0		0		0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member] \| State and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0		0		0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member] \| U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0		0		0
Recurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member] \| CRA Investments Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	0	0		0		0
Recurring [Member] \| Mortgage Servicing Rights [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	2,797	3,030	3,235	3,236	2,968	2,968
Total recognized gains (losses) included in net income	118		(228)	(422)	(37)
Issues	167		146	388	443
Settlements	(118)		(123)	(238)	(344)
Ending balance	2,964	3,236	3,030	2,964	3,030	3,236
Total gains (losses) for the period included in net income attributable to the change in unrealized gains or losses related to assets still held at the reporting date	118		(228)	(422)	(37)
Nonrecurring [Member]
Impaired loan (collateral dependent) [Abstract]
Impaired loans, fair value adjustments	300	1,000	300	600	900	1,800
Other real estate owned [Abstract]
Other real estate /assets owned, fair value adjustment	400	500	$ 800	600	$ 1,100	1,700
Nonrecurring [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	4,824	3,192		4,824		3,192
Other real estate /assets owned	2,687	6,798		2,687		6,798
Nonrecurring [Member] \| Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	0	0		0		0
Other real estate /assets owned	0	0		0		0
Nonrecurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	0	0		0		0
Other real estate /assets owned	0	0		0		0
Nonrecurring [Member] \| Significant Unobservable Inputs (Level 3) [Member] \| Fair Value [Member]
Assets measured-nonrecurring basis [Abstract]
Impaired loans (collateral dependent)	4,824	3,192		4,824		3,192
Other real estate /assets owned	$ 2,687	$ 6,798		$ 2,687		$ 6,798