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, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	$ 879,862,000	$ 1,279,137,000
Trading Securities, Change in Unrealized Holding Gain (Loss)	27,217,000	(27,015,000)	$ 92,226,000
Investments	4,462,430,000	4,298,686,000
Securities (Assets)
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities, Change in Unrealized Holding Gain (Loss)	16,800,000	(25,200,000)
US government and agency securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	33,042,000	129,913,000
State and municipal obligations
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	259,573,000	303,946,000
Corporate bonds and notes
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	453,617,000	580,993,000
RMBS
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	38,214,000	72,192,000
CMBS
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	78,984,000	137,678,000
Other ABS
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	8,219,000	16,131,000
Foreign government securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	8,213,000	13,268,000
Foreign government securities \| Portugal, Ireland, Italy, Greece, Spain and Hungary Government Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Investments	0	0
Equity securities
Schedule of Trading Securities and Other Trading Assets [Line Items]
Trading Securities	$ 0	$ 25,016,000