Note 2. Investment Securities: Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	$ 335,792	$ 130,045
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	14,937	1,683
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	63,529	22,199
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	5,132	814
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	399,321	152,244
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	20,069	2,497
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year	126	45
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year	27	23
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	153	68
Domestic Corporate Debt Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	124,531	61,386
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	5,340	953
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	21,070
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	2,127
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	145,601	61,386
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	7,467	953
Residential Mortgage Backed Securities Member
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	2,047	2,416
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	8	21
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		1,138
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss		44
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	2,047	3,554
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	8	65
Commercial Mortgage Backed Securities
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	593	570
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	382	405
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	593	570
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	382	405
US Treasury Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	493	5,667
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	6	2
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	493	5,667
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	6	2
US Government-sponsored Enterprises Debt Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	22,731	6,162
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	123	40
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	5,360	2,784
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	217	27
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	28,091	8,946
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	340	67
US States and Political Subdivisions Debt Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	149,704	53,036
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	7,312	657
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	32,983	17,707
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	2,065	338
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	182,687	70,743
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	9,377	995
Foreign Government Debt
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	27,587
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	1,766
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	3,523
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	341
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	31,110
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	2,107
Redeemable Preferred Stock
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	3,485
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	278
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	3,485
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	278
Debt Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	330,578	128,667
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	14,833	1,673
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	63,529	22,199
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	5,132	814
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	394,107	150,866
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	19,965	2,487
COMMON STOCK
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	2,589
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	70
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	2,589
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	70
Nonredeemable Preferred Stock
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	2,625	1,378
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	34	10
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	2,625	1,378
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	34	10
Equity Securities
Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	5,214	1,378
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	104	10
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	5,214	1,378
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss	$ 104	$ 10