| Cover | 6 Months Ended |
| Jun. 30, 2021 | |
| Document Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Jan. 27, 2022 |
| Entity Registrant Name | LCNB CORP. |
| Entity Tax Identification Number | 31-1626393 |
| Entity Incorporation, State or Country Code | OH |
| Entity File Number | 001-35292 |
| Entity Address, Address Line One | 2 North Broadway |
| Entity Address, State or Province | OH |
| Entity Address, City or Town | Lebanon |
| Entity Address, Postal Zip Code | 45036 |
| City Area Code | (513) |
| Local Phone Number | 932-1414 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, No Par Value |
| Trading Symbol | LCNB |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001074902 |
