Note 5 - Investments Net Gains (Losses) on Investments and Other Financial Instruments (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Gain (Loss) on Securities [Line Items]
Other gains (losses), net realized gain (loss)		$ 85	$ 12
Net realized gains (losses) on investments		(1,687)	(3,442)
Unrealized Gain (Loss) on Securities		19,469	(12,804)
Total net gains (losses) on investments		17,782	(17,090)
Net gains (losses) on other financial instruments		4,131	(1,797)
Net gains (losses) on investments and other financial instruments		21,913	(18,887)
Fixed maturities
Gain (Loss) on Securities [Line Items]
Fixed maturities available for sale, net realized gain (loss)	[1]	(495)	(3,120)
Gross investment gains from sales and redemptions		4,165	598
Gross investment losses from sales and redemptions		(4,660)	(3,718)
Equity securities
Gain (Loss) on Securities [Line Items]
Equity securities, net realized gain (loss)		(680)	142
Trading Securities
Gain (Loss) on Securities [Line Items]
Trading securities, net realized gain (loss)		(684)	(538)
Other invested assets
Gain (Loss) on Securities [Line Items]
Other invested assets, net realized gain (loss)		$ 87	$ 62

[1] Components of net realized gains (losses) on fixed-maturities available for sale include:   Three Months Ended
March 31, (In thousands) 2019   2018 Gross investment gains from sales and redemptions $ 4,165
  $ 598
Gross investment losses from sales and redemptions (4,660 )   (3,718 )