XML 55 R45.htm IDEA: XBRL DOCUMENT
v3.23.3

Loans and Allowance for Credit Losses - Allowance for off-balance credit exposure (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Sep. 30, 2023 | Sep. 30, 2022
Allowance for off-balance sheet credit exposure: |  |
Balance, beginning of period | $ 6,288 | $ 3,358
Provision (benefit) charged to expense | (670) | 806
Balance, end of period | 5,618 | 4,164
Residential Real Estate |  |
Allowance for off-balance sheet credit exposure: |  |
Balance, beginning of period | 71 | 58
Provision (benefit) charged to expense | 7 | 135
Balance, end of period | 78 | 193
Construction Real Estate |  |
Allowance for off-balance sheet credit exposure: |  |
Balance, beginning of period | 4,809 | 2,178
Provision (benefit) charged to expense | (616) | 719
Balance, end of period | 4,193 | 2,897
Commercial Real Estate |  |
Allowance for off-balance sheet credit exposure: |  |
Balance, beginning of period | 475 | 421
Provision (benefit) charged to expense | (10) | 107
Balance, end of period | 465 | 528
Consumer loans |  |
Allowance for off-balance sheet credit exposure: |  |
Balance, beginning of period | 73 | 61
Provision (benefit) charged to expense | (2) |
Balance, end of period | 71 | 61
Commercial loans |  |
Allowance for off-balance sheet credit exposure: |  |
Balance, beginning of period | 860 | 640
Provision (benefit) charged to expense | (49) | (155)
Balance, end of period | $ 811 | $ 485

X
- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482454/460-10-45-1 + Details
Name: | us-gaap_OffBalanceSheetCreditLossLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 + Details
Name: | us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_OffBalanceSheetCreditLossLiabilityRollforward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=smbc_ConstructionPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |