XML 47 R37.htm IDEA: XBRL DOCUMENT
v3.25.3

Organization and Summary of Significant Accounting Policies - Loans (Details) | 3 Months Ended
--- | ---
Sep. 30, 2025 item
Organization and Summary of Significant Accounting Policies |
Number of loan portfolio pools | 23

X
- Definition Represents the number of loan portfolio segments. + References No definition available. + Details
Name: | smbc_NumberOfLoanSegments
Namespace Prefix: | smbc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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