XML 74 R58.htm IDEA: XBRL DOCUMENT
v3.25.2

Organization and Summary of Significant Accounting Policies - Wealth Management Assets and Fees (Details) - USD ($) $ in Millions | Jun. 30, 2025 | Jun. 30, 2024
--- | --- | ---
Organization and Summary of Significant Accounting Policies |  |
Fiduciary assets | $ 107.6 | $ 100.9
Investment management assets | $ 538.2 | $ 474.7

X
- Definition The carrying amount as of the balance sheet date of fiduciary assets. + References No definition available. + Details
Name: | smbc_FiduciaryAssets
Namespace Prefix: | smbc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition The carrying amount of assets an investment adviser manages on behalf of investors. + References No definition available. + Details
Name: | us-gaap_AssetsUnderManagementCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant