Value of input used to measure allowance for credit losses.

No definition available.

Name:	lcnb_AllowanceForCreditLossesMeasurementInput
Namespace Prefix:	lcnb_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

The amortization period for the financing receivable

+ References

No definition available.

+ Details

Name:	lcnb_FinancingReceivableAmortizationPeriod
Namespace Prefix:	lcnb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

+ References

No definition available.

+ Details

Name:	lcnb_FinancingReceivableModifiedSubsequentDefaultNumberOfLoans
Namespace Prefix:	lcnb_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The duration of the balloon payment for financing receivable.

+ References

No definition available.

+ Details

Name:	lcnb_FinancingReceivablePeriodicPaymentTermsBalloonPaymentPeriod
Namespace Prefix:	lcnb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

The duration on the adjustment period for he variable rates of interest

+ References

No definition available.

+ Details

Name:	lcnb_FinancingReceivableVariableRatesOfInterestAdjustmentPeriod
Namespace Prefix:	lcnb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

The ratio of the loan to appraised value

+ References

No definition available.

+ Details

Name:	lcnb_LoanAndLeaseReceivableRatioOfLoanToAppraisedValue
Namespace Prefix:	lcnb_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

The term length for the loans and leases receivable

+ References

No definition available.

+ Details

Name:	lcnb_LoansAndLeasesReceivableTerm
Namespace Prefix:	lcnb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

The unpaid principle balance of loans serviced for others

+ References

No definition available.

+ Details

Name:	lcnb_UnpaidPrincipalBalanceOfLoansServicedForOthers
Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage of allowance for credit loss to total financing receivable outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph a
-Subparagraph (1)
-Publisher SEC

+ Details

Name:	srt_FinancingReceivableAllowanceForCreditLossToOutstandingPercent
Namespace Prefix:	srt_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of nonaccrual to total financing receivable outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph a
-Subparagraph (2)
-Publisher SEC

+ Details

Name:	srt_FinancingReceivableNonaccrualToOutstandingPercent
Namespace Prefix:	srt_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A

+ Details

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

- Definition

Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3A

+ Details

Name:	us-gaap_FinancingReceivableAccruedInterestAfterAllowanceForCreditLossStatementOfFinancialPositionExtensibleList
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of writeoff of accrued interest on financing receivable recognized by reversing interest income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3D
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3D

+ Details

Name:	us-gaap_FinancingReceivableAccruedInterestWriteoff
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amortized cost excluding accrued interest, of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 44
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-44

+ Details

Name:	us-gaap_FinancingReceivableExcludingAccruedInterestModifiedSubsequentDefault
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest income on financing receivable on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

+ Details

Name:	us-gaap_FinancingReceivableNonaccrualInterestIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481598/310-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-4

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-SubTopic 20
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481569/310-20-50-3

+ Details

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

- Definition

Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481746/310-40-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 36
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-36

+ Details

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

- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 35
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-35

+ Details

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

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=lcnb_FederalHomeLoanMortgageCorporationAndOtherInvestorsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=lcnb_HomeEquityLineofcreditLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=lcnb_CommercialAndIndustrialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=lcnb_UnemploymentRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_ArithmeticAverageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=lcnb_CoincidentEconomicActivityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=lcnb_CommercialRealEstatePriceIndexesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MeasurementInputTypeAxis=lcnb_HomePriceIndexMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 4 - Loans (Details Textual) $ in Thousands	3 Months Ended
Note 4 - Loans (Details Textual) $ in Thousands	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
Financing Receivable, Unamortized Loan Cost (Fee)	$ 929		$ 796
Financing Receivable, Accrued Interest, after Allowance for Credit Loss	7,900		$ 7,700
Financing Receivable, Nonaccrual, Interest Income	1	$ 116
Financing Receivable, Accrued Interest, Writeoff	$ 9	$ 27
Financing Receivable, Nonaccrual to Outstanding, Percent	0.27%		0.26%
Financing Receivable, Allowance for Credit Loss to Outstanding, Percent	0.71%		0.70%
Mortgage Loans in Process of Foreclosure, Amount	$ 60		$ 33
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default	0
Financing Receivable, Modified, Commitment to Lend	$ 0		$ 0
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Other Assets		Other Assets
Federal Home Loan Mortgage Corporation and Other Investors [Member]
Unpaid Principal Balance Of Loans Serviced For Others	$ 354,600		$ 397,600
Residential Portfolio Segment [Member] \| Home Equity Line-of-credit loans [Member]
Financing Receivable, Amortization Period (Year)	5 years
Consumer Portfolio Segment [Member]
Financing Receivable, Modified, Subsequent Default, Number of Loans	2
Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default	$ 27
Minimum [Member] \| Commercial and Industrial Portfolio Segment [Member]
Loans and Leases Receivable, Term (Year)	1 year
Minimum [Member] \| Commercial Real Estate Portfolio Segment [Member]
Loans and Leases Receivable, Term (Year)	5 years
Financing Receivable, Periodic Payment Terms, Balloon Payment Period (Year)	1 year
Financing Receivable, Variable Rates Of Interest, Adjustment Period (Year)	1 year
Loan And Lease Receivable, Ratio Of Loan To Appraised Value	0.75
Minimum [Member] \| Residential Portfolio Segment [Member]
Financing Receivable, Variable Rates Of Interest, Adjustment Period (Year)	1 year
Loan And Lease Receivable, Ratio Of Loan To Appraised Value	0.80
Financing Receivable, Amortization Period (Year)	5 years
Maximum [Member] \| Commercial and Industrial Portfolio Segment [Member]
Loans and Leases Receivable, Term (Year)	10 years
Maximum [Member] \| Commercial Real Estate Portfolio Segment [Member]
Loans and Leases Receivable, Term (Year)	25 years
Financing Receivable, Periodic Payment Terms, Balloon Payment Period (Year)	10 years
Financing Receivable, Variable Rates Of Interest, Adjustment Period (Year)	10 years
Loan And Lease Receivable, Ratio Of Loan To Appraised Value	0.85
Maximum [Member] \| Residential Portfolio Segment [Member]
Financing Receivable, Variable Rates Of Interest, Adjustment Period (Year)	15 years
Financing Receivable, Amortization Period (Year)	30 years
Maximum [Member] \| Consumer Portfolio Segment [Member]
Loans and Leases Receivable, Term (Year)	72 months
Unemployment Rate [Member] \| Minimum [Member]
Allowance for Credit Losses, Measurement Input	4.66		4.75
Unemployment Rate [Member] \| Maximum [Member]
Allowance for Credit Losses, Measurement Input	5.57		5.48
Unemployment Rate [Member] \| Arithmetic Average [Member]
Allowance for Credit Losses, Measurement Input	(5.73)
Coincident Economic Activity [Member] \| Minimum [Member]
Allowance for Credit Losses, Measurement Input	0.43		(0.21)
Coincident Economic Activity [Member] \| Maximum [Member]
Allowance for Credit Losses, Measurement Input	1.18		0.008
Coincident Economic Activity [Member] \| Arithmetic Average [Member]
Allowance for Credit Losses, Measurement Input	(1.94)
Commercial Real Estate Price Indexes [Member] \| Minimum [Member]
Allowance for Credit Losses, Measurement Input	(8.9)		(0.0695)
Commercial Real Estate Price Indexes [Member] \| Maximum [Member]
Allowance for Credit Losses, Measurement Input	(2.3)		(0.0207)
Commercial Real Estate Price Indexes [Member] \| Arithmetic Average [Member]
Allowance for Credit Losses, Measurement Input	4.65
Home Price Index [Member] \| Minimum [Member]
Allowance for Credit Losses, Measurement Input	(1.54)		(0.0251)
Home Price Index [Member] \| Maximum [Member]
Allowance for Credit Losses, Measurement Input	3.08		0.0291
Home Price Index [Member] \| Arithmetic Average [Member]
Allowance for Credit Losses, Measurement Input	(2.78)