Note 23: Accumulated Other Comprehensive Income: Schedule of Amounts Reclassified from Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	$ 0	$ 1,830	$ 1
Affected Line Item in the Statements of Income | Net realized gains on available-for-sale securities (total reclassified amount before tax)
Unrealized gains on available-for-sale securities reclassified out of AOCI	0	2,873	2
Affected Line Item in the Statements of Income | Tax (expense) benefit
Income taxes on unrealized gains on available-for-sale securities reclassified out of AOCI	$ 0	$ (1,043)	$ (1)