| Cover | Oct. 27, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Oct. 27, 2020 |
| Entity File Number | 000-27719 |
| Entity Registrant Name | Southern First Bancshares, Inc. |
| Entity Central Index Key | 0001090009 |
| Entity Tax Identification Number | 58-2459561 |
| Entity Incorporation, State or Country Code | SC |
| Entity Address, Address Line One | 100 Verdae Boulevard |
| Entity Address, Address Line Two | Suite 100 |
| Entity Address, City or Town | Greenville |
| Entity Address, State or Province | SC |
| Entity Address, Postal Zip Code | 29607 |
| City Area Code | 864 |
| Local Phone Number | 679-9000 |
| 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 | SFST |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Information, Former Legal or Registered Name | Not Applicable |
