| Cover | Apr. 24, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Jul. 22, 2020 |
| Entity Registrant Name | COLONY BANKCORP, INC. |
| Entity Incorporation, State or Country Code | GA |
| Entity File Number | 000-12436 |
| Entity Tax Identification Number | 58-1492391 |
| Entity Address, Address Line One | 115 South Grant Street |
| Entity Address, City or Town | Fitzgerald |
| Entity Address, State or Province | GA |
| Entity Address, Postal Zip Code | 31750 |
| City Area Code | 229 |
| Local Phone Number | 426-6000 |
| 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 $1.00 per share |
| Trading Symbol | CBAN |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000711669 |
| Amendment Flag | false |
