Sum of the carrying amounts as of the balance sheet date of all investments.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Amount of unrealized holding gain (loss) recognized in the income statement for investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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Note 6 - Investments Investments Trading Securities (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	$ 1,279,137,000	$ 1,633,584,000
Trading Securities, Change in Unrealized Holding Gain (Loss)	(27,015,000)	92,226,000	$ (117,198,000)
Investments	4,298,686,000	3,629,299,000
Securities (Assets)
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities, Change in Unrealized Holding Gain (Loss)	25,200,000	65,700,000
US government and agency securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	129,913,000	134,530,000
State and municipal obligations
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	303,946,000	343,926,000
Corporate bonds and notes
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	580,993,000	708,361,000
RMBS
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	72,192,000	89,810,000
CMBS
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	137,678,000	188,615,000
Other ABS
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	16,131,000	77,755,000
Foreign government securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	13,268,000	18,331,000
Equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	25,016,000	72,256,000
Portugal, Ireland, Italy, Greece, Spain and Hungary Government Securities [Member] \| Foreign government securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Investments	$ 0	$ 0