Note 12 - Fair Value Measurements - Quantitative Information About Unobservable Inputs for Assets Measured on a Nonrecurring Basis Using Level 3 Measurements (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Impaired Loans [Member]
Fair Value	$ 3,055	$ 6,397
OREO [Member]
Fair Value	4,158	6,187
Fair Value, Inputs, Level 3 [Member] \| Impaired Loans [Member]
Fair Value	3,055	6,397
Fair Value, Inputs, Level 3 [Member] \| OREO [Member]
Fair Value	4,158	6,187
Fair Value, Inputs, Level 3 [Member] \| Income Approach Valuation Technique [Member] \| Impaired Loans [Member]
Fair Value	$ 3,055	$ 6,397
Valuation Technique	Discounted appraisals	Discounted appraisals
Unobservable Inputs	Marketability discount	Marketability discount
Fair Value, Inputs, Level 3 [Member] \| Income Approach Valuation Technique [Member] \| Impaired Loans [Member] \| Minimum [Member]
Marketability Discount	1.10%	0.00%
Fair Value, Inputs, Level 3 [Member] \| Income Approach Valuation Technique [Member] \| Impaired Loans [Member] \| Maximum [Member]
Marketability Discount	22.80%	67.80%
Fair Value, Inputs, Level 3 [Member] \| Income Approach Valuation Technique [Member] \| Impaired Loans [Member] \| Weighted Average [Member]
Marketability Discount	9.70%	3.50%
Fair Value, Inputs, Level 3 [Member] \| Income Approach Valuation Technique [Member] \| OREO [Member]
Fair Value	$ 4,158	$ 6,187
Valuation Technique	Discounted appraisals	Discounted appraisals
Unobservable Inputs	Marketability discount	Marketability discount
Fair Value, Inputs, Level 3 [Member] \| Income Approach Valuation Technique [Member] \| OREO [Member] \| Minimum [Member]
Marketability Discount	0.00%	0.00%
Fair Value, Inputs, Level 3 [Member] \| Income Approach Valuation Technique [Member] \| OREO [Member] \| Maximum [Member]
Marketability Discount	52.40%	50.00%
Fair Value, Inputs, Level 3 [Member] \| Income Approach Valuation Technique [Member] \| OREO [Member] \| Weighted Average [Member]
Marketability Discount	17.50%	11.20%

This item represents a description of the valuation technique used to measure fair value using significant unobservable inputs (Level 3) as applied to the identified category of asset.

No definition available.

+ Details

Name:	ffkt_FairValueDescriptionValuationTechnique
Namespace Prefix:	ffkt_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_AssetsFairValueDisclosureNonrecurring
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

+ 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 (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the inputs and valuation technique(s) used to measure fair value.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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- Details

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- Details

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- Details

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