Note 4: Loans and Allowance for Loan Losses: Performing Loans Classified as Troubled Debt Restructuring Loans (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($)	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Jun. 30, 2018	Jun. 30, 2017 USD ($)
Residential Mortgage
Financing Receivable, Modifications, Number of Contracts	4	1	4	1
Construction Real Estate
Financing Receivable, Modifications, Number of Contracts	0	0	0	1
Commercial Real Estate
Financing Receivable, Modifications, Number of Contracts	1	0	1	4
Consumer Loan
Financing Receivable, Modifications, Number of Contracts	2	1	2	3
Commercial Loan
Financing Receivable, Modifications, Number of Contracts	2	0	2	1
Total loans
Financing Receivable, Modifications, Number of Contracts	9	2	9	10
Performing Financial Instruments | Residential Mortgage
Financing Receivable, Modifications, Number of Contracts	12				10
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 809					$ 1,756
Performing Financial Instruments | Construction Real Estate
Financing Receivable, Modifications, Number of Contracts	0				0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 0					0
Performing Financial Instruments | Commercial Real Estate
Financing Receivable, Modifications, Number of Contracts	13				13
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 8,101					5,206
Performing Financial Instruments | Consumer Loan
Financing Receivable, Modifications, Number of Contracts	2				0
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 26					0
Performing Financial Instruments | Commercial Loan
Financing Receivable, Modifications, Number of Contracts	8				6
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 2,911					3,946
Performing Financial Instruments | Total loans
Financing Receivable, Modifications, Number of Contracts	35				29
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 11,847					$ 10,908