XML 105 R92.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Fair Value Accounting (Details Textual) | 12 Months Ended
--- | ---
Dec. 31, 2017
Fair Value Accounting (Textual) |
Percentage of loans collateralize by real estate | More than 80%.

X
- References No definition available. + Details
Name: | sfst_FairValueAccountingTextualAbstract
Namespace Prefix: | sfst_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of company's loans collateral by real estate. + References No definition available. + Details
Name: | sfst_PercentageOfLoansCollateralByRealEstate
Namespace Prefix: | sfst_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration