| Document and Entity Information | Oct. 22, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Oct. 22, 2020 |
| Entity File Number | 001-38483 |
| Entity Registrant Name | BAYCOM CORP |
| Entity Incorporation, State or Country Code | CA |
| Entity Tax Identification Number | 37-1849111 |
| Entity Address, Address Line One | 500 Ygnacio Valley Road |
| Entity Address, Adress Line Two | Suite 200 |
| Entity Address, City or Town | Walnut Creek |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94596 |
| City Area Code | 925 |
| Local Phone Number | 476-1800 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | BCML |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Entity Central Index Key | 0001730984 |
| Amendment Flag | false |
