Note 15: Disclosures About Fair Value of Financial Instruments: Schedule of Fair Value, Assets Measured on Recurring Basis (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
US Government Agencies Debt Securities
Assets, Fair Value Disclosure, Recurring	$ 30,040	$ 20,060
Other Observable Inputs (Level 2)	30,040	20,060
Collateralized Mortgage Backed Securities
Assets, Fair Value Disclosure, Recurring	4,507	4,840
Other Observable Inputs (Level 2)	4,507	4,840
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Assets, Fair Value Disclosure, Recurring	596,086	641,655
Other Observable Inputs (Level 2)	596,086	641,655
Small Business Administration loan pools
Assets, Fair Value Disclosure, Recurring	51,493	56,492
Other Observable Inputs (Level 2)	51,493	56,492
US States and Political Subdivisions Debt Securities
Assets, Fair Value Disclosure, Recurring	122,878	150,238
Other Observable Inputs (Level 2)	122,878	150,238
Equity Securities
Assets, Fair Value Disclosure, Recurring	2,006	1,831
Quoted Prices in Active Markets for Identical Assets (Level 1)		387
Other Observable Inputs (Level 2)	2,006	1,444
Mortgage servicing rights
Assets, Fair Value Disclosure, Recurring	152	292
Significant Unobservable Inputs (Level 3)	152	292
Interest rate swap asset
Assets, Fair Value Disclosure, Recurring	2,112	111
Significant Unobservable Inputs (Level 3)	2,112	111
Interest rate swap liability
Assets, Fair Value Disclosure, Recurring	(2,160)	(121)
Significant Unobservable Inputs (Level 3)	(2,160)	(121)
Corporate Bond Securities
Assets, Fair Value Disclosure, Recurring		295
Other Observable Inputs (Level 2)		$ 295