Note 4. Investment Securities: Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value (Details) $ in Thousands	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	$ 89,235	$ 210,357
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	791	3,709
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	89,761	91,565
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	3,962	4,512
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	178,996	301,922
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 4,753	$ 8,221
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year	27	99
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year	29	31
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	56	130
Corporate Debt Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	$ 20,570	$ 101,903
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	83	2,559
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	54,794	55,217
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	3,135	3,309
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	75,364	157,120
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	3,218	5,868
US Treasury Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	28,247	19,809
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1	64
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	28,247	19,809
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	1	64
US Government-sponsored Enterprises Debt Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value		6,539
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		128
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	10,520	4,997
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	162	126
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	10,520	11,536
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	162	254
US States and Political Subdivisions Debt Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	31,983	68,898
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	256	780
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	24,447	31,351
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	665	1,077
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	56,430	100,249
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	921	1,857
Foreign Government Debt
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	3,253	484
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	42	6
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	3,253	484
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	42	6
Redeemable Preferred Stock
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	3,358	3,749
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	404	14
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	3,358	3,749
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	404	14
Debt Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	87,411	204,249
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	786	3,565
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	89,761	91,565
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	3,962	4,512
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	177,172	295,814
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	4,748	8,077
COMMON STOCK, AMOUNT
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	501	4,784
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	1	142
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	501	4,784
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	1	142
Nonredeemable Preferred Stock
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	1,323	1,324
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	4	2
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1,323	1,324
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	4	2
Equity Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	1,824	6,108
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	5	144
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1,824	6,108
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 5	144
Residential Mortgage Backed Securities Member
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value		2,867
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		14
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		2,867
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		$ 14

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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