Note 4: Loans and Allowance for Loan Losses: Performing Loans Classified as Troubled Debt Restructuring Loans (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)
Consumer Loan
modifications	0	0
Investment	$ 0	$ 0
Commercial Loan
modifications	0	1
Investment	$ 0	$ 69
Construction Loan Payable
modifications	0	0
Investment	$ 0	$ 0
Residential Real Estate
modifications	0	0
Investment	$ 0	$ 0
Commercial Real Estate
modifications	0	2
Investment	$ 0	$ 922
Performing Loans
modifications	38		40
Investment	$ 12,432		$ 13,289
Performing Loans | Consumer Loan
modifications	0		0
Investment	$ 0		$ 0
Performing Loans | Commercial Loan
modifications	9		10
Investment	$ 4,872		$ 5,630
Performing Loans | Construction Loan Payable
modifications	0		0
Investment	$ 0		$ 0
Performing Loans | Residential Real Estate
modifications	11		10
Investment	$ 1,162		$ 1,130
Performing Loans | Commercial Real Estate
modifications	18		20
Investment	$ 6,398		$ 6,529
Total Loans
modifications	0	3
Investment	$ 0	$ 991