Note 2: Investments in Securities: Mortgage-backed securities portfolio (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Fixed rates of interest
Agency collateralized mortgage obligations	$ 149,900
Mortgage-backed securities	144,300
Variable rates of interest
Agency collateralized mortgage obligations	2,100
Mortgage-backed securities	20,700
Federal National Mortgage Association Certificates and Obligations (FNMA)
Agency mortgage-backed securities	147,600
Agency collateralized mortgage obligations	23,900
Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC)
Agency mortgage-backed securities	13,300
Agency collateralized mortgage obligations	5,400
Government National Mortgage Association Certificates and Obligations (GNMA)
Agency mortgage-backed securities	4,100
Agency collateralized mortgage obligations	$ 122,700