Note 15: Disclosures About Fair Value of Financial Instruments: Fair Value, Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Recurring Assets, Fair Value Disclosure	$ 174,022	$ 165,042
Collateralized Mortgage Obligations
Recurring Assets, Fair Value Disclosure	179,833	151,950
US States and Political Subdivisions Debt Securities
Recurring Assets, Fair Value Disclosure	71,203	35,125
Small Business Administration securities
Recurring Assets, Fair Value Disclosure	21,877	22,058
Interest rate derivative asset
Recurring Assets, Fair Value Disclosure	6,580	31,476
Interest rate derivative liability
Recurring Assets, Fair Value Disclosure	(7,221)	(1,547)
Fair Value, Inputs, Level 1 | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 | Collateralized Mortgage Obligations
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 | US States and Political Subdivisions Debt Securities
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 | Small Business Administration securities
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 | Interest rate derivative asset
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 1 | Interest rate derivative liability
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Recurring Assets, Fair Value Disclosure	174,022	165,042
Fair Value, Inputs, Level 2 | Collateralized Mortgage Obligations
Recurring Assets, Fair Value Disclosure	179,833	151,950
Fair Value, Inputs, Level 2 | US States and Political Subdivisions Debt Securities
Recurring Assets, Fair Value Disclosure	71,203	35,125
Fair Value, Inputs, Level 2 | Small Business Administration securities
Recurring Assets, Fair Value Disclosure	21,877	22,058
Fair Value, Inputs, Level 2 | Interest rate derivative asset
Recurring Assets, Fair Value Disclosure	6,580	31,476
Fair Value, Inputs, Level 2 | Interest rate derivative liability
Recurring Assets, Fair Value Disclosure	(7,221)	(1,547)
Fair Value, Inputs, Level 3 | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 | Collateralized Mortgage Obligations
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 | US States and Political Subdivisions Debt Securities
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 | Small Business Administration securities
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 | Interest rate derivative asset
Recurring Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 | Interest rate derivative liability
Recurring Assets, Fair Value Disclosure	$ 0	$ 0