Note 2: Investments in Securities: Schedule of Financial Instruments Owned and Pledged as Collateral (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Securities Pledged as Collateral
Securities Owned and Pledged As Collateral Amortized Cost	$ 133,159	$ 163,227
Security Owned and Pledged as Collateral, Fair Value	132,867	163,393
Public deposits
Securities Owned and Pledged As Collateral Amortized Cost	10,958	57,841
Security Owned and Pledged as Collateral, Fair Value	11,490	59,082
Collateralized Loan Obligations
Securities Owned and Pledged As Collateral Amortized Cost	120,622	98,787
Security Owned and Pledged as Collateral, Fair Value	119,776	97,498
Collateralized Securities, Other
Securities Owned and Pledged As Collateral Amortized Cost	1,579	6,599
Security Owned and Pledged as Collateral, Fair Value	$ 1,601	$ 6,813