| Cover | Mar. 18, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Mar. 18, 2021 |
| Entity Registrant Name | CB FINANCIAL SERVICES, INC. |
| Entity File Number | 001-36706 |
| Entity Incorporation, State or Country Code | PA |
| Entity Tax Identification Number | 51-0534721 |
| Entity Address, Address Line One | 100 N. Market Street, |
| Entity Address, City or Town | Carmichaels, |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 15320 |
| City Area Code | (724) |
| Local Phone Number | 966-5041 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common stock, par value $0.4167 per share |
| Trading Symbol | CBFV |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001605301 |
| Amendment Flag | false |
