FAIR VALUE OF FINANCIAL INSTRUMENTS, AT FAIR VALUE (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Recurring fair value measurements
Investment securities available-for-sale:
U.S. Treasury notes	$ 62,560	$ 12,894
U.S. Agency notes	83,637	106,675
U.S. Agency mortgage-backed securities	38,032	40,309
Certificate of Deposit, Fair Value Disclosure	3,086	1,501
Municipal securities:
Non-taxable	77,395	75,333
Taxable	16,395	17,309
Mutual funds	2,461	2,380
Trust preferred securities	50	147
Equity securities	1,749	1,693
Total recurring fair value measurements	285,365	258,241
Recurring fair value measurements \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Investment securities available-for-sale:
U.S. Treasury notes	62,560	12,894
U.S. Agency notes	0	0
U.S. Agency mortgage-backed securities	0	0
Certificate of Deposit, Fair Value Disclosure	0	0
Municipal securities:
Non-taxable	0	0
Taxable	0	0
Mutual funds	1,461	1,380
Trust preferred securities	50	147
Equity securities	1,749	1,693
Total recurring fair value measurements	65,820	16,114
Recurring fair value measurements \| Significant Other Observable Inputs (Level 2)
Investment securities available-for-sale:
U.S. Treasury notes	0	0
U.S. Agency notes	83,637	106,675
U.S. Agency mortgage-backed securities	38,032	40,309
Certificate of Deposit, Fair Value Disclosure	3,086	1,501
Municipal securities:
Non-taxable	77,395	75,333
Taxable	16,395	17,309
Mutual funds	1,000	1,000
Trust preferred securities	0	0
Equity securities	0	0
Total recurring fair value measurements	219,545	242,127
Recurring fair value measurements \| Significant Unobservable Inputs (Level 3)
Investment securities available-for-sale:
U.S. Treasury notes	0	0
U.S. Agency notes	0	0
U.S. Agency mortgage-backed securities	0	0
Certificate of Deposit, Fair Value Disclosure	0	0
Municipal securities:
Non-taxable	0	0
Taxable	0	0
Mutual funds	0	0
Trust preferred securities	0	0
Equity securities	0	0
Total recurring fair value measurements	0	0
Nonrecurring fair value measurements
Nonrecurring fair value measurements:
Impaired loans	4,872	8,530
Other real estate owned and repossessed assets	1,370	1,463
Total nonrecurring fair value measurements	6,242	9,993
Nonrecurring fair value measurements \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Nonrecurring fair value measurements:
Impaired loans	0	0
Other real estate owned and repossessed assets	0	0
Total nonrecurring fair value measurements	0	0
Nonrecurring fair value measurements \| Significant Other Observable Inputs (Level 2)
Nonrecurring fair value measurements:
Impaired loans	0	773
Other real estate owned and repossessed assets	0	1,463
Total nonrecurring fair value measurements	0	2,236
Nonrecurring fair value measurements \| Significant Unobservable Inputs (Level 3)
Nonrecurring fair value measurements:
Impaired loans	4,872	7,757
Other real estate owned and repossessed assets	1,370	0
Total nonrecurring fair value measurements	$ 6,242	$ 7,757

No definition available.

Name:	lcnb_AvailableForSaleMutualFundsFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in equity securities which are categorized as Available-for-sale.

+ References

No definition available.

+ Details

Name:	lcnb_AvailableForSaleSecuritiesEquitySecuritiesFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	lcnb_AvailableForSaleSecuritiesMunicipalNonTaxableFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	lcnb_AvailableForSaleSecuritiesTaxableMunicipalsFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	lcnb_AvailableForSaleTrustPreferredSecuritiesFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of a savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate.

+ References

No definition available.

+ Details

Name:	lcnb_CertificateOfDepositFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This element represents the fair value disclosure of impaired loans that have had a fair value adjustment since their initial recognition.

+ References

No definition available.

+ Details

Name:	lcnb_ImpairedLoansFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	lcnb_MunicipalSecuritiesAbstract
Namespace Prefix:	lcnb_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	lcnb_NonrecurringFairValueMeasurementsAbstract
Namespace Prefix:	lcnb_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the fair value disclosure of other real estate owned and valued at fair value upon transfer from loans. These items are marked down to fair value at the time they are transferred from loans.

+ References

No definition available.

+ Details

Name:	lcnb_OtherRealEstateOwnedAndRepossessedAssetsFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	lcnb_UnitedStatesGovernmentAgencyDebtSecuritiesAvailableForSaleFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	lcnb_UnitedStatesGovernmentAgencyMortgageBackedSecuritiesAvailableForSaleFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	lcnb_USTreasuryNotesDebtDisclosureAvailableForSaleFairValueDisclosure
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring 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_AssetsFairValueDisclosureRecurring
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: