Regulatory Matters (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Tier I capital (to average assets), Amount [Abstract]
Actual Amount	$ 496,432	$ 468,304
For Capital Adequacy Purposes	$ 155,743	$ 151,066
Tier I capital (to average assets), Ratio [Abstract]
Actual Ratio	12.75%	12.40%
For Capital Adequacy Purposes	4.00%	4.00%
Common equity Tier 1 capital (to risk weighted assets), Amount [Abstract]
Actual Amount	$ 436,932	$ 408,804
For Capital Adequacy Purposes	$ 129,525	$ 126,194
Common equity Tier 1 capital (to risk weighted assets), Ratio [Abstract]
Actual Ratio	15.18%	14.58%
For Capital Adequacy Purposes	4.50%	4.50%
Tier I capital (to risk weighted assets), Amount [Abstract]
Actual Amount	$ 496,432	$ 468,304
For Capital Adequacy Purposes	$ 172,672	$ 168,253
Tier I capital (to risk weighted assets), Ratio [Abstract]
Actual Ratio	17.25%	16.70%
For Capital Adequacy Purposes	6.00%	6.00%
Total capital (to risk weighted assets), Amount [Abstract]
Actual Amount	$ 532,332	$ 503,296
For Capital Adequacy Purposes	$ 230,198	$ 224,310
Total capital (to risk-weighted assets), Ratio [Abstract]
Actual Ratio	18.50%	17.95%
For Capital Adequacy Purposes	8.00%	8.00%
Community Trust Bank, Inc [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Maximum dividend without Approval	$ 55,400
Tier I capital (to average assets), Amount [Abstract]
Actual Amount	472,615	$ 445,107
For Capital Adequacy Purposes	155,083	150,374
To Be Well-Capitalized Under Prompt Corrective Action Provision	$ 193,854	$ 187,967
Tier I capital (to average assets), Ratio [Abstract]
Actual Ratio	12.19%	11.84%
For Capital Adequacy Purposes	4.00%	4.00%
To Be Well-Capitalized Under Prompt Corrective Action Provision	5.00%	5.00%
Common equity Tier 1 capital (to risk weighted assets), Amount [Abstract]
Actual Amount	$ 472,615	$ 445,107
For Capital Adequacy Purposes	129,208	125,895
To Be Well-Capitalized Under Prompt Corrective Action Provision	$ 186,634	$ 181,848
Common equity Tier 1 capital (to risk weighted assets), Ratio [Abstract]
Actual Ratio	16.46%	15.91%
For Capital Adequacy Purposes	4.50%	4.50%
To Be Well-Capitalized Under Prompt Corrective Action Provision	6.50%	6.50%
Tier I capital (to risk weighted assets), Amount [Abstract]
Actual Amount	$ 472,615	$ 445,107
For Capital Adequacy Purposes	172,278	167,859
To Be Well-Capitalized Under Prompt Corrective Action Provision	$ 229,704	$ 223,812
Tier I capital (to risk weighted assets), Ratio [Abstract]
Actual Ratio	16.46%	15.91%
For Capital Adequacy Purposes	6.00%	6.00%
To Be Well-Capitalized Under Prompt Corrective Action Provision	8.00%	8.00%
Total capital (to risk weighted assets), Amount [Abstract]
Actual Amount	$ 508,515	$ 480,099
For Capital Adequacy Purposes	229,708	223,822
To Be Well-Capitalized Under Prompt Corrective Action Provision	$ 287,134	$ 279,778
Total capital (to risk-weighted assets), Ratio [Abstract]
Actual Ratio	17.71%	17.16%
For Capital Adequacy Purposes	8.00%	8.00%
To Be Well-Capitalized Under Prompt Corrective Action Provision	10.00%	10.00%