Note 6 - Investments Gain (Loss) on Investments (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
		Jun. 30, 2015	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Gain (Loss) on Investments [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held			$ 0		$ 0		$ 0
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Period Increase (Decrease)					0		0
Fixed-maturities available for sale	[1]		(3,014)		4,160		(1,176)
Equities available for sale		$ 69,200	368	[2]	(170)	[2]	69,150	[2],[3]
Trading securities			(5,995)		(237)		(9,231)
Short-term investments			(16)		(135)		(24)
Other invested assets			22		631		3,267
Gain (Loss) on Disposition of Other Assets			32		64		110
Net realized gains (losses) on investments			(8,603)		4,313		62,096
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net			(1,420)		(526)		0
Unrealized gains (losses) on trading securities			13,230		27,217		(27,015)
Net gains (losses) on investments			3,207		31,004		35,081
Net gains (losses) on other financial instruments			414		(253)		612
Net Gains/Losses on All Financial Instruments			3,621		30,751		35,693
Other Comprehensive Income (Loss) [Member]
Gain (Loss) on Investments [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities Continuing Operations, before Tax		$ 69,200
Debt Securities [Member]
Gain (Loss) on Investments [Line Items]
Other than Temporary Impairment Losses, Investments			400
Debt and Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Other than Temporary Impairment Losses, Investments			1,000
Fixed Maturities [Member]
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Gross Realized Gains			6,052		10,326		64
Available-for-sale Securities, Gross Realized Losses			(9,066)		$ (6,166)		$ (1,240)
Convertible Debt Securities [Member]
Gain (Loss) on Investments [Line Items]
Other than Temporary Impairment Losses, Investments			500
Equity securities
Gain (Loss) on Investments [Line Items]
Other than Temporary Impairment Losses, Investments			$ 500

[1] Components of net realized gains (losses) on fixed-maturities available for sale include: Year Ended December 31,(In thousands)2017 2016 2015Gross investment gains from sales and redemptions$6,052 $10,326 $64Gross investment losses from sales and redemptions(9,066) (6,166) (1,240)

[2] Net realized gains (losses) on equities available for sale is equal to the gross amount of gains and losses, respectively, realized for those periods.

[3] During the second quarter of 2015, we sold equity securities in our portfolio and reinvested the proceeds in assets that qualify as PMIERs-compliant Available Assets, recognizing pretax gains of $69.2 million.