XML 43 R32.htm IDEA: XBRL DOCUMENT
v3.25.2

Loans and Allowance for Credit Losses (Details) - Schedule of composition of our loan portfolio - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2025 | Dec. 31, 2024
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 3,746,841 | $ 3,631,767
Total loans percentage | 100.00% | 100.00%
Less - allowance for credit losses | $ (41,285) | $ (39,914)
Total loans, net | 3,705,556 | 3,591,853
Commercial [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 2,283,669 | $ 2,235,285
Total loans percentage | 60.90% | 61.50%
Commercial [Member] | Construction [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 68,421 | $ 103,204
Total loans percentage | 1.80% | 2.80%
Commercial [Member] | Business [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 589,661 | $ 556,117
Total loans percentage | 15.70% | 15.30%
Commercial [Member] | Owner occupied RE [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 686,424 | $ 651,597
Total loans percentage | 18.30% | 17.90%
Commercial [Member] | Non-owner occupied RE [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 939,163 | $ 924,367
Total loans percentage | 25.10% | 25.50%
Consumer [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 1,463,172 | $ 1,396,482
Total loans percentage | 39.10% | 38.50%
Consumer [Member] | Construction [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 25,210 | $ 20,874
Total loans percentage | 0.60% | 0.60%
Consumer [Member] | Real estate [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 1,164,187 | $ 1,128,629
Total loans percentage | 31.10% | 31.10%
Consumer [Member] | Home equity [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 234,608 | $ 204,897
Total loans percentage | 6.30% | 5.60%
Consumer [Member] | Other [Member] |  |
Financing Receivable, Past Due [Line Items] |  |
Total loans | $ 39,167 | $ 42,082
Total loans percentage | 1.10% | 1.20%

X
- Definition Total percentage of deferred loan fees and costs of commercial loans. + References No definition available. + Details
Name: | SFST_CommercialLoansReceivablePercentage
Namespace Prefix: | SFST_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total percentage of deferred loan fees and costs of consumer loans. + References No definition available. + Details
Name: | SFST_ConsumerLoansReceivablePercentage
Namespace Prefix: | SFST_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loans and leases receivable net of deferred income percentage. + References No definition available. + Details
Name: | SFST_LoansAndLeasesReceivableNetOfDeferredIncomePercentage
Namespace Prefix: | SFST_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11B -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph c -Publisher SEC Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph a -Subparagraph (1) -Publisher SEC Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph a -Subparagraph (3) -Publisher SEC Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (d)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (d)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (d)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (d)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 8: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 9: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 10: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-14 Reference 12: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (e)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 13: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (e)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 14: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (b)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 15: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 16: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-12 Reference 17: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 80 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-80 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482736/825-10-45-1A Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 948 -SubTopic 310 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477011/948-310-45-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481990/310-10-45-13 Reference 5: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-7A Reference 6: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 29 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-29 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph a -Subparagraph (1) -Publisher SEC Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph a -Subparagraph (2) -Publisher SEC Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef -Name Regulation S-K (SK) -Number 229 -Section 1404 -Paragraph a -Publisher SEC Reference 10: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 80 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-80 Reference 11: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479294/326-20-55-79 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-14 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-5 + Details
Name: | us-gaap_NotesReceivableGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481990/310-10-45-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(5)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479170/946-210-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-5 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(3)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
Name: | us-gaap_NotesReceivableNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CommercialLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConstructionLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=SFST_BusinessLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_ConsumerLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_RealEstateLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HomeEquityLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=SFST_OtherConsumerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |