XML 55 R45.htm IDEA: XBRL DOCUMENT
v3.22.1

Loans and Allowance for Credit Losses (Details) - Schedule of allowance for loan losses and recorded investment in loans by impairment methodology - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Allowance For Loan Losses [Member] |  |
Loans and Allowance for Credit Losses (Details) - Schedule of allowance for loan losses and recorded investment in loans by impairment methodology [Line Items] |  |
Individually evaluated | $ 1,635 | $ 836
Collectively evaluated | 41,864 | 29,572
Total | 43,499 | 30,408
Recorded Investment In Loans [Member] |  |
Loans and Allowance for Credit Losses (Details) - Schedule of allowance for loan losses and recorded investment in loans by impairment methodology [Line Items] |  |
Individually evaluated | 12,182 | 8,163
Collectively evaluated | 2,171,500 | 2,481,714
Total | 2,183,682 | 2,489,877
Commercial [Member] | Allowance For Loan Losses [Member] |  |
Loans and Allowance for Credit Losses (Details) - Schedule of allowance for loan losses and recorded investment in loans by impairment methodology [Line Items] |  |
Individually evaluated | 1,171 | 623
Collectively evaluated | 28,853 | 20,107
Total | 30,024 | 20,730
Commercial [Member] | Recorded Investment In Loans [Member] |  |
Loans and Allowance for Credit Losses (Details) - Schedule of allowance for loan losses and recorded investment in loans by impairment methodology [Line Items] |  |
Individually evaluated | 5,967 | 3,435
Collectively evaluated | 1,382,616 | 1,549,837
Total | 1,388,583 | 1,553,272
Consumer [Member] | Allowance For Loan Losses [Member] |  |
Loans and Allowance for Credit Losses (Details) - Schedule of allowance for loan losses and recorded investment in loans by impairment methodology [Line Items] |  |
Individually evaluated | 464 | 213
Collectively evaluated | 13,011 | 9,465
Total | 13,475 | 9,678
Consumer [Member] | Recorded Investment In Loans [Member] |  |
Loans and Allowance for Credit Losses (Details) - Schedule of allowance for loan losses and recorded investment in loans by impairment methodology [Line Items] |  |
Individually evaluated | 6,215 | 4,728
Collectively evaluated | 788,884 | 931,877
Total | $ 795,099 | $ 936,605

X
- References No definition available. + Details
Name: | sfst_CollectivelyEvaluated
Namespace Prefix: | sfst_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | sfst_IndividuallyEvaluated
Namespace Prefix: | sfst_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | sfst_InvestmentOnLoansTotal
Namespace Prefix: | sfst_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Details
Name: | us-gaap_ShortTermDebtTypeAxis=sfst_AllowanceForLoanLossesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortTermDebtTypeAxis=sfst_RecordedOnIvestmentInLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=sfst_CommercialMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=sfst_ConsumerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |