| Cover | Jul. 22, 2021 | Apr. 22, 2021 |
| Cover [Abstract] | ||
| Document Type | 8-K | |
| Document Period End Date | Jul. 22, 2021 | |
| 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 | true | |
| Soliciting Material | true | |
| 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 |
