XML 101 R85.htm IDEA: XBRL DOCUMENT
v3.25.2

Deposits - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Jun. 30, 2025 | Jun. 30, 2024
Deposits |  |
Aggregate amount of deposits with a minimum denomination of $250,000 | $ 1,400.0 | $ 1,200.0
Brokered certificates | 233.6 | 171.8
Deposits from affiliates | $ 14.4 | $ 6.5

X
- Definition Represents the monetary amount of Aggregate Amount of Deposits With a Minimum Denomination of $250,000, as of the indicated date. + References No definition available. + Details
Name: | smbc_AggregateAmountOfDepositsWithAMinimumDenominationOf250000
Namespace Prefix: | smbc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Represents the monetary amount of Deposits Held for Affiliates, during the indicated time period. + References No definition available. + Details
Name: | smbc_DepositsHeldForAffiliates
Namespace Prefix: | smbc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Definition Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(12)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 + Details
Name: | us-gaap_InterestBearingDomesticDepositBrokered
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant