Note 3: Securities: Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020
US States and Political Subdivisions Debt Securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	$ 531
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	531
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	1
Other Debt Obligations
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0	$ 995
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	5
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	839	643
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	327	338
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	839	1,638
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	327	343
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	8,368	9,037
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	43	39
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	8,368	9,037
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	43	39
Total investments and mortgage-backed securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	8,899	10,032
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	44	44
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	839	643
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	327	338
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	9,738	10,675
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 371	$ 382