Note 26: Summary of Unaudited Quarterly Operating Results: Schedule of Quarterly Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net income													$ 67,109	$ 51,564	$ 45,342
Quarterly operating results
Interest Income, Operating	$ 56,142	$ 52,982	$ 49,943	$ 46,882	$ 46,536	$ 46,368	$ 44,744	$ 45,413	$ 46,937	$ 46,856	$ 45,636	$ 45,746
Interest Expense Operating	11,585	9,997	8,731	7,444	7,263	7,087	6,843	6,712	6,690	5,828	4,974	4,627
Provision for Other Losses	1,950	1,300	1,950	1,950	1,950	2,950	1,950	2,250	2,380	2,500	2,300	2,101
Net realized gain (losses) and impairment on available for sale securities operating	0	2	0	0	0	0	0	0	(9)	144	2,735	3
Noninterest Income, Other Operating Income	7,220	14,604	7,459	6,935	7,374	7,655	15,800	7,698	7,530	7,090	8,916	4,974
Other Noninterest Expense	28,774	28,309	29,915	28,312	29,283	28,034	28,371	28,573	29,043	30,657	29,807	30,920
Provision for income taxes	3,765	5,464	2,967	2,645	3,207	4,289	7,204	4,058	4,560	3,740	4,937	3,279
Net income available to common shareholders	$ 17,288	$ 22,516	$ 13,839	$ 13,466	$ 12,207	$ 11,663	$ 16,176	$ 11,518	$ 11,794	$ 11,221	$ 12,534	$ 9,793
Earnings per share operating results diluted	$ 1.21	$ 1.57	$ 0.97	$ 0.95	$ 0.86	$ 0.82	$ 1.14	$ 0.81	$ 0.83	$ 0.80	$ 0.89	$ 0.70
Net income					$ 12,207	$ 11,663	$ 16,176	$ 11,518	$ 11,794	$ 11,221	$ 12,534	$ 9,793