Loans, Troubled Debt Restructuring (Details)	3 Months Ended
Mar. 31, 2022 USD ($) Bank_Loan	Mar. 31, 2021 USD ($) Bank_Loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Bank_Loan	0	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 21,000
Financing Receivable, Troubled Debt Restructuring, Postmodification	0	21,000
Loan modifications classified as troubled debt restructurings [Abstract]
Troubled debt restructurings that subsequently defaulted within 12 months of the restructuring date	0	0
Financing Receivable, Modifications, with No Related Allowance, Recorded Investment	0	21,000
Financing Receivable, Modifications, with Related Allowance, Recorded Investment - Details	$ 0	$ 0
Commercial and industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Bank_Loan	0	0
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 0
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 0
Commercial, secured by real estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Bank_Loan	0	0
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 0
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 0
Residential real estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Bank_Loan	0	1
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 21,000
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 21,000
Consumer [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts \| Bank_Loan	0	0
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 0
Financing Receivable, Troubled Debt Restructuring, Postmodification	$ 0	$ 0

Financing Receivable, Modifications, with No Related Allowance, Recorded Investment

No definition available.

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

- Definition

Financing Receivable, Modifications, with Related Allowance, Recorded Investment - Details

+ References

No definition available.

+ Details

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Namespace Prefix:	lcnb_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

-- None. No documentation exists for this element. --

+ References

No definition available.

+ Details

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

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

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

+ Details

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

- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

+ Details

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

- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

+ Details

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

- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

+ Details

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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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