Note 3: Loans and Allowance For Loan Losses: Construction Lending Policy: Construction Loans Modified for other than TDR (Details) - Construction Loans $ in Thousands	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)
Number of Loans Modified for Other Than TDR	49	31
Amount of Loans Modified for Other Than TDR	$ 8,200	$ 13,100

Represents the monetary amount of Amount of Loans Modified for Other Than TDR, as of the indicated date.

No definition available.

Name:	smbc_AmountOfLoansModifiedForOtherThanTdr
Namespace Prefix:	smbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant