NOTE 6: LOANS AND ALLOWANCE FOR LOAN LOSSES: Impaired Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Automobile Loan
Impaired Financing Receivable, Recorded Investment	$ 1,843	$ 2,740	$ 1,843	$ 2,740	$ 2,713
Impaired Financing Receivable, Unpaid Principal Balance	2,046	2,936	2,046	2,936	2,898
Impaired Financing Receivable, Related Allowance	331	491	331	491	484
Impaired Financing Receivable, Average Recorded Investment	1,865	2,548	2,120	2,323	2,383
Impaired Financing Receivable Interest Income Recognized	37	79	118	156	222
One-to-Four-Family Residential Construction
Impaired Financing Receivable, Recorded Investment	0	0	0	0	0
Impaired Financing Receivable, Unpaid Principal Balance	0	0	0	0	0
Impaired Financing Receivable, Related Allowance	0	0	0	0	0
Impaired Financing Receivable, Average Recorded Investment	0	0	0	258	193
Impaired Financing Receivable Interest Income Recognized	0	0	0	0	0
Subdivision Construction
Impaired Financing Receivable, Recorded Investment	241	434	241	434	349
Impaired Financing Receivable, Unpaid Principal Balance	241	450	241	450	367
Impaired Financing Receivable, Related Allowance	107	116	107	116	114
Impaired Financing Receivable, Average Recorded Investment	299	444	336	652	584
Impaired Financing Receivable Interest Income Recognized	3	9	11	21	22
Land Development
Impaired Financing Receivable, Recorded Investment	14	315	14	315	15
Impaired Financing Receivable, Unpaid Principal Balance	18	319	18	319	18
Impaired Financing Receivable, Related Allowance	0	0	0	0	0
Impaired Financing Receivable, Average Recorded Investment	15	424	15	2,319	1,793
Impaired Financing Receivable Interest Income Recognized	1	12	1	33	24
Commercial Construction
Impaired Financing Receivable, Recorded Investment	0	0	0	0	0
Impaired Financing Receivable, Unpaid Principal Balance	0	0	0	0	0
Impaired Financing Receivable, Related Allowance	0	0	0	0	0
Impaired Financing Receivable, Average Recorded Investment	0	0	0	0	0
Impaired Financing Receivable Interest Income Recognized	0	0	0	0	0
Owner Occupied One-to-Four-Family Residential
Impaired Financing Receivable, Recorded Investment	3,663	3,441	3,663	3,441	3,405
Impaired Financing Receivable, Unpaid Principal Balance	3,995	3,740	3,995	3,740	3,723
Impaired Financing Receivable, Related Allowance	343	351	343	351	331
Impaired Financing Receivable, Average Recorded Investment	3,401	3,440	3,322	3,384	3,405
Impaired Financing Receivable Interest Income Recognized	53	44	142	124	166
Non-Owner Occupied One To Four Family Residential
Impaired Financing Receivable, Recorded Investment	2,398	3,293	2,398	3,293	3,196
Impaired Financing Receivable, Unpaid Principal Balance	2,677	3,560	2,677	3,560	3,465
Impaired Financing Receivable, Related Allowance	321	104	321	104	68
Impaired Financing Receivable, Average Recorded Investment	2,583	2,550	3,082	2,183	2,419
Impaired Financing Receivable Interest Income Recognized	38	80	130	128	165
Commercial Real Estate
Impaired Financing Receivable, Recorded Investment	3,556	9,358	3,556	9,358	8,315
Impaired Financing Receivable, Unpaid Principal Balance	3,714	9,581	3,714	9,581	8,490
Impaired Financing Receivable, Related Allowance	635	599	635	599	599
Impaired Financing Receivable, Average Recorded Investment	6,689	6,819	7,115	9,068	9,075
Impaired Financing Receivable Interest Income Recognized	55	266	278	425	567
Other Residential
Impaired Financing Receivable, Recorded Investment	0	3,390	0	3,390	2,907
Impaired Financing Receivable, Unpaid Principal Balance	0	3,390	0	3,390	2,907
Impaired Financing Receivable, Related Allowance	0	0	0	0	0
Impaired Financing Receivable, Average Recorded Investment	675	3,457	1,368	3,660	3,553
Impaired Financing Receivable Interest Income Recognized	0	27	20	102	147
Commercial Business
Impaired Financing Receivable, Recorded Investment	2,008	3,141	2,008	3,141	3,018
Impaired Financing Receivable, Unpaid Principal Balance	2,383	4,311	2,383	4,311	4,222
Impaired Financing Receivable, Related Allowance	324	2,396	324	2,396	2,140
Impaired Financing Receivable, Average Recorded Investment	2,581	5,580	3,277	6,148	5,384
Impaired Financing Receivable Interest Income Recognized	40	35	329	161	173
Industrial Revenue Bonds
Impaired Financing Receivable, Recorded Investment	0	0	0	0	0
Impaired Financing Receivable, Unpaid Principal Balance	0	0	0	0	0
Impaired Financing Receivable, Related Allowance	0	0	0	0	0
Impaired Financing Receivable, Average Recorded Investment	0	0	0	0	0
Impaired Financing Receivable Interest Income Recognized	0	0	0	0	0
Consumer Loan
Impaired Financing Receivable, Recorded Investment	566	1,042	566	1,042	825
Impaired Financing Receivable, Unpaid Principal Balance	751	1,148	751	1,148	917
Impaired Financing Receivable, Related Allowance	85	156	85	156	124
Impaired Financing Receivable, Average Recorded Investment	671	1,005	806	886	906
Impaired Financing Receivable Interest Income Recognized	11	26	48	65	69
Home Equity Line of Credit
Impaired Financing Receivable, Recorded Investment	115	647	115	647	591
Impaired Financing Receivable, Unpaid Principal Balance	133	725	133	725	648
Impaired Financing Receivable, Related Allowance	17	100	17	100	91
Impaired Financing Receivable, Average Recorded Investment	405	633	500	456	498
Impaired Financing Receivable Interest Income Recognized	0	14	28	32	33
Loans Receivable
Impaired Financing Receivable, Recorded Investment	14,404	27,801	14,404	27,801	25,334
Impaired Financing Receivable, Unpaid Principal Balance	15,958	30,160	15,958	30,160	27,655
Impaired Financing Receivable, Related Allowance	2,163	4,313	2,163	4,313	3,951
Impaired Financing Receivable, Average Recorded Investment	19,184	26,900	21,941	31,337	30,193
Impaired Financing Receivable Interest Income Recognized	$ 238	$ 592	$ 1,105	$ 1,247	$ 1,588