LOANS, IMPAIRED LOANS (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
With no related allowance recorded [Abstract]
Recorded Investment	$ 18,357	$ 21,899
Unpaid Principal Balance	21,061	25,851
Average Recorded Investment	20,918	24,831	$ 30,678
Interest Income Recognized	1,902	3,482	1,990
With an allowance recorded [Abstract]
Recorded Investment	5,810	5,087
Unpaid Principal Balance	6,066	5,329
Related Allowance	469	363
Average Recorded Investment	5,229	5,241	5,471
Interest Income Recognized	315	172	182
Total [Abstract]
Recorded Investment	24,167	26,986
Unpaid Principal Balance	27,127	31,180
Average Recorded Investment	26,147	30,072	36,149
Interest Income Recognized	2,217	3,654	2,172
Interest income recognized on a cash basis	51	96	8
Commercial & industrial
With no related allowance recorded [Abstract]
Recorded Investment	109	1,205
Unpaid Principal Balance	263	1,500
Average Recorded Investment	998	1,467	1,823
Interest Income Recognized	151	206	161
With an allowance recorded [Abstract]
Recorded Investment	326	356
Unpaid Principal Balance	326	356
Related Allowance	9	9
Average Recorded Investment	341	370	319
Interest Income Recognized	19	21	19
Total [Abstract]
Recorded Investment	435	1,561
Unpaid Principal Balance	589	1,856
Average Recorded Investment	1,339	1,837	2,142
Interest Income Recognized	170	227	180
Commercial, secured by real estate
With no related allowance recorded [Abstract]
Recorded Investment	14,195	16,345
Unpaid Principal Balance	15,522	18,335
Average Recorded Investment	15,274	18,575	23,360
Interest Income Recognized	1,140	2,229	1,373
With an allowance recorded [Abstract]
Recorded Investment	4,690	3,883
Unpaid Principal Balance	4,946	4,014
Related Allowance	347	306
Average Recorded Investment	4,194	4,007	4,108
Interest Income Recognized	257	114	117
Total [Abstract]
Recorded Investment	18,885	20,228
Unpaid Principal Balance	20,468	22,349
Average Recorded Investment	19,468	22,582	27,468
Interest Income Recognized	1,397	2,343	1,490
Residential real estate
With no related allowance recorded [Abstract]
Recorded Investment	3,238	3,734
Unpaid Principal Balance	4,286	5,055
Average Recorded Investment	3,736	4,092	4,645
Interest Income Recognized	369	453	379
With an allowance recorded [Abstract]
Recorded Investment	751	846
Unpaid Principal Balance	751	958
Related Allowance	100	48
Average Recorded Investment	651	864	1,026
Interest Income Recognized	36	37	44
Total [Abstract]
Recorded Investment	3,989	4,580
Unpaid Principal Balance	5,037	6,013
Average Recorded Investment	4,387	4,956	5,671
Interest Income Recognized	405	490	423
Consumer
With no related allowance recorded [Abstract]
Recorded Investment	26	81
Unpaid Principal Balance	27	109
Average Recorded Investment	37	106	179
Interest Income Recognized	29	25	14
With an allowance recorded [Abstract]
Recorded Investment	43	2
Unpaid Principal Balance	43	1
Related Allowance	13	0
Average Recorded Investment	43	0	18
Interest Income Recognized	3	0	2
Total [Abstract]
Recorded Investment	69	83
Unpaid Principal Balance	70	110
Average Recorded Investment	80	106	197
Interest Income Recognized	32	25	16
Agricultural
With no related allowance recorded [Abstract]
Recorded Investment	334	48
Unpaid Principal Balance	334	151
Average Recorded Investment	392	81	121
Interest Income Recognized	136	487	20
With an allowance recorded [Abstract]
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	0	0
Interest Income Recognized	0	0	0
Total [Abstract]
Recorded Investment	334	48
Unpaid Principal Balance	334	151
Average Recorded Investment	392	81	121
Interest Income Recognized	136	487	20
Other
With no related allowance recorded [Abstract]
Recorded Investment	455	486
Unpaid Principal Balance	629	701
Average Recorded Investment	481	510	550
Interest Income Recognized	77	82	43
With an allowance recorded [Abstract]
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	0	0
Interest Income Recognized	0	0	0
Total [Abstract]
Recorded Investment	455	486
Unpaid Principal Balance	629	701
Average Recorded Investment	481	510	550
Interest Income Recognized	$ 77	$ 82	$ 43

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

No definition available.

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

+ Details

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

- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

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

- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

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

- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

+ Details

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

- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

+ Details

Name:	us-gaap_ImpairedFinancingReceivableRelatedAllowance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

+ Details

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

- Definition

Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

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

- Definition

Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired.

+ References

+ Details

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

- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

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

- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

+ Details

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

- Details

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

- Details

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