Note 3: Loans and Allowance For Loan Losses: Loans Modified in Troubled Debt Restructurings by Segment (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Troubled Debt Restructurings Total Modifications	$ 15,000	$ 21,100	$ 45,000
Total Troubled Debt Restructurings Accruing Interest	$ 12,300	18,600	39,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0
Substandard
Troubled Debt Restructurings	$ 8,800	7,900	12,200
Construction And Land Development
Troubled Debt Restructurings Total Modifications		429
Troubled Debt Restructured Loans and Impaired	266,000	5,000	7,900
Single Family and Multi-Family Residential Mortgage Loans
Troubled Debt Restructured Loans and Impaired	6,200	7,400	13,500
Commercial Real Estate
Troubled Debt Restructured Loans and Impaired	7,100	7,100	21,300
Commercial Business
Troubled Debt Restructurings Total Modifications	290	38	1,095
Troubled Debt Restructured Loans and Impaired	867	1,300	2,000
Consumer Loan
Troubled Debt Restructurings Total Modifications	245	59	97
Troubled Debt Restructured Loans and Impaired	$ 617	$ 296	$ 311