Note 8: Loss Sharing Agreements and FDIC Indemnification Assets: InterBank Business Combination Policy (Details) (InterBank, USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2012	Apr. 27, 2012
InterBank
Business Acquisition Fair Value Assumed Deposits			$ 456,300,000
Business Acquisition Fair Value Purchased Loans			285,500,000
Business Acquisition Fair Value Foreclosed Assets			6,200,000
Business Acquisition Foreclosed Assets Discount			59,900,000
Acquired Loans Premium and Amount Amortized to Yield	$ (68,000)	$ 126,000