Note 3: Loans and Allowance For Loan Losses: Purchaed Credit Impaired Loans included in Nonaccrual Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Jun. 30, 2014
Included in Nonaccrual Loans
Purchased Credit Impaired Loans	$ 2,400	$ 0

Represents the monetary amount of Purchased Credit Impaired Loans, as of the indicated date.

No definition available.

Name:	smbc_PurchasedCreditImpairedLoans
Namespace Prefix:	smbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant