Note 3: Loans and Allowance For Loan Losses: Impaired Financing Receivables (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
One To Four Family Residential Construction
Impaired Financing Receivable, Recorded Investment	$ 0	$ 0	$ 0
Impaired Financing Receivable, Unpaid Principal Balance	0	0	0
Impaired Financing Receivable, Related Allowance	0	0	0
Impaired Financing Receivable, Average Recorded Investment	193	0	633
Impaired Financing Receivable Interest Income Recognized	0	0	35
Subdivision Construction
Impaired Financing Receivable, Recorded Investment	349	818	1,061
Impaired Financing Receivable, Unpaid Principal Balance	367	829	1,061
Impaired Financing Receivable, Related Allowance	114	131	214
Impaired Financing Receivable, Average Recorded Investment	584	948	3,533
Impaired Financing Receivable Interest Income Recognized	22	46	109
Land Development
Impaired Financing Receivable, Recorded Investment	15	6,023	7,555
Impaired Financing Receivable, Unpaid Principal Balance	18	6,120	7,644
Impaired Financing Receivable, Related Allowance	0	1,291	1,391
Impaired Financing Receivable, Average Recorded Investment	1,793	8,020	7,432
Impaired Financing Receivable Interest Income Recognized	24	304	287
Commercial Construction
Impaired Financing Receivable, Recorded Investment	0	0	0
Impaired Financing Receivable, Unpaid Principal Balance	0	0	0
Impaired Financing Receivable, Related Allowance	0	0	0
Impaired Financing Receivable, Average Recorded Investment	0	0	0
Impaired Financing Receivable Interest Income Recognized	0	0	0
Owner Occupied One To Four Family Residential
Impaired Financing Receivable, Recorded Investment	3,405	3,290	3,166
Impaired Financing Receivable, Unpaid Principal Balance	3,723	3,555	3,427
Impaired Financing Receivable, Related Allowance	331	374	389
Impaired Financing Receivable, Average Recorded Investment	3,405	3,267	3,587
Impaired Financing Receivable Interest Income Recognized	166	182	179
Non-Owner Occupied One To Four Family Residential
Impaired Financing Receivable, Recorded Investment	3,196	1,907	1,902
Impaired Financing Receivable, Unpaid Principal Balance	3,465	2,177	2,138
Impaired Financing Receivable, Related Allowance	68	65	128
Impaired Financing Receivable, Average Recorded Investment	2,419	1,886	1,769
Impaired Financing Receivable Interest Income Recognized	165	113	100
Commercial Real Estate
Impaired Financing Receivable, Recorded Investment	8,315	10,507	34,629
Impaired Financing Receivable, Unpaid Principal Balance	8,490	12,121	37,259
Impaired Financing Receivable, Related Allowance	599	2,209	2,556
Impaired Financing Receivable, Average Recorded Investment	9,075	23,928	28,610
Impaired Financing Receivable Interest Income Recognized	567	984	1,594
Other Residential
Impaired Financing Receivable, Recorded Investment	2,907	3,812	9,533
Impaired Financing Receivable, Unpaid Principal Balance	2,907	3,812	9,533
Impaired Financing Receivable, Related Allowance	0	0	0
Impaired Financing Receivable, Average Recorded Investment	3,553	6,813	9,670
Impaired Financing Receivable Interest Income Recognized	147	258	378
Commercial Business
Impaired Financing Receivable, Recorded Investment	3,018	4,539	2,365
Impaired Financing Receivable, Unpaid Principal Balance	4,222	4,652	2,539
Impaired Financing Receivable, Related Allowance	2,140	1,295	1,115
Impaired Financing Receivable, Average Recorded Investment	5,384	2,542	2,268
Impaired Financing Receivable Interest Income Recognized	173	185	138
Industrial Revenue Bonds
Impaired Financing Receivable, Recorded Investment	0	0	0
Impaired Financing Receivable, Unpaid Principal Balance	0	0	0
Impaired Financing Receivable, Related Allowance	0	0	0
Impaired Financing Receivable, Average Recorded Investment	0	0	0
Impaired Financing Receivable Interest Income Recognized	0	0	0
Automobile Loan
Impaired Financing Receivable, Recorded Investment	2,713	2,097	791
Impaired Financing Receivable, Unpaid Principal Balance	2,898	2,178	829
Impaired Financing Receivable, Related Allowance	484	629	119
Impaired Financing Receivable, Average Recorded Investment	2,383	1,307	576
Impaired Financing Receivable Interest Income Recognized	222	141	59
Consumer Loan
Impaired Financing Receivable, Recorded Investment	825	812	802
Impaired Financing Receivable, Unpaid Principal Balance	917	887	885
Impaired Financing Receivable, Related Allowance	124	244	120
Impaired Financing Receivable, Average Recorded Investment	906	884	672
Impaired Financing Receivable Interest Income Recognized	69	70	74
Home Equity Line of Credit
Impaired Financing Receivable, Recorded Investment	591	476	357
Impaired Financing Receivable, Unpaid Principal Balance	648	492	374
Impaired Financing Receivable, Related Allowance	91	124	61
Impaired Financing Receivable, Average Recorded Investment	498	417	403
Impaired Financing Receivable Interest Income Recognized	33	32	27
Loans Receivable Impaired
Impaired Financing Receivable, Recorded Investment	25,334	34,281	62,161
Impaired Financing Receivable, Unpaid Principal Balance	27,655	36,823	65,689
Impaired Financing Receivable, Related Allowance	3,951	6,362	6,093
Impaired Financing Receivable, Average Recorded Investment	30,193	50,012	59,153
Impaired Financing Receivable Interest Income Recognized	$ 1,588	$ 2,315	$ 2,980