Note 10: Retirement Plans: Noncontributory Employee Stock Ownership Plan (ESOP) (Details) - EmployeeStockOwnershipPlanESOPMember	12 Months Ended
	Dec. 31, 2016 shares
Employee Stock Ownership Plan (ESOP), Plan Description	The Company and its subsidiaries have a noncontributory Employee Stock Ownership Plan (“ESOP”) for all eligible employees. Eligible employees are primarily those with more than one year of service, who work in excess of 1,000 hours per year. Contributions, which may be in cash or stock of the Company, are determined annually by the Board of Directors. The Company’s contributions are allocated to eligible employees based on the ratio of each eligible employee’s compensation to total compensation for all eligible employees during each year.
Class A Common Stock
Employee Stock Ownership Plan (ESOP), Shares in ESOP	500,450
Class C Common Stock
Employee Stock Ownership Plan (ESOP), Shares in ESOP	265,623