Note 2: Investments in Debt and Equity Securities: Schedule of Collateralized Mortgage Obligations and Mortgage-Backed Securities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Fixed Rate
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	$ 16,217
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	1,541
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	17,758
Hybrid ARM
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	565,822
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	13,320
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Losses	814
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	578,328
Collateralized Mortgage Backed Securities | Nonagency Variable
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	3,939
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	576
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Losses	8
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	4,507
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	41,913
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	3,190
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	45,103
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Federal National Mortgage Association Certificates and Obligations (FNMA)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	59,930
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	2,644
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Losses	302
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	62,272
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Government National Mortgage Association Certificates and Obligations (GNMA)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	480,196
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	9,027
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Losses	512
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	488,711
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Fixed Rate | Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	6,482
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	696
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	7,178
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Fixed Rate | Federal National Mortgage Association Certificates and Obligations (FNMA)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	9,728
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	845
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	10,573
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Fixed Rate | Government National Mortgage Association Certificates and Obligations (GNMA)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	7
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	7
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Hybrid ARM | Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	35,431
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	2,494
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	37,925
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Hybrid ARM | Federal National Mortgage Association Certificates and Obligations (FNMA)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	50,202
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	1,799
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Losses	302
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	51,699
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises | Hybrid ARM | Government National Mortgage Association Certificates and Obligations (GNMA)
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	480,189
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	9,027
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Losses	512
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	488,704
Total Mortgage Obligations
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	582,039
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	14,861
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Losses	814
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	596,086
Total Fixed and Hybrid ARM Mortgage Obligations
Collateralized Mortgage Obligations and Mortgage-Backed Securities Amortized Cost	582,039
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Gains	14,861
Collateralized Mortgage Obligations and Mortgage-Backed Securities Gross Unrealized Losses	814
Collateralized Mortgage Obligations and Mortgage-Backed Securities Fair Value	$ 596,086