Note 14 - Accumulated Other Comprehensive Income Rollforward of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Other Comprehensive Income, Net of Tax [Abstract]
AOCI, Net of Tax, beginning balance				$ (12,395)
Unrealized holding gains (losses) arising during the period		$ 6,239	$ 6,943	33,845	$ 86,614
Less: Reclassification adjustment for net gains (losses) included in net income (loss)		111	3,695	(2,687)	2,296
Net foreign currency translation adjustments		28	(36)	136	(346)
Net actuarial gains (losses)		0	156	0	(22)
Other comprehensive income, net of tax		6,156	3,368	36,668	83,950
AOCI, Net of Tax, ending balance		24,273		24,273
Other Comprehensive Income
Other Comprehensive Income, before Tax [Abstract]
AOCI before Tax, Attributable to Parent, beginning balance		27,878	95,548	(19,063)	(28,425)
Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax		9,598	10,682	52,069	133,253
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax	[1]	170	5,685	(4,134)	3,533
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax		9,428	4,997	56,203	129,720
Net foreign currency translation adjustments, before tax		39	(47)	205	(523)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax			240		(34)
Other comprehensive income, before tax		9,467	5,190	56,408	129,163
AOCI before Tax, Attributable to Parent, ending balance		37,345	100,738	37,345	100,738
Other Comprehensive Income, Tax [Abstract]
AOCI, Tax, beginning balance		9,761	33,443	(6,668)	(9,948)
Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax		3,359	3,739	18,224	46,639
Less: Reclassification adjustment for net (losses) gains included in net income, tax	[1]	59	1,990	(1,447)	1,237
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax		3,300	1,749	19,671	45,402
Net foreign currency translation adjustments, tax		11	(11)	69	(177)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, Tax			84		(12)
Other Comprehensive Income, Tax		3,311	1,822	19,740	45,213
AOCI Tax, ending balance		13,072	35,265	13,072	35,265
Other Comprehensive Income, Net of Tax [Abstract]
AOCI, Net of Tax, beginning balance		18,117	62,105	(12,395)	(18,477)
Unrealized holding gains (losses) arising during the period		6,239	6,943	33,845	86,614
Less: Reclassification adjustment for net gains (losses) included in net income (loss)	[1]	111	3,695	(2,687)	2,296
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent		6,128	3,248	36,532	84,318
Net foreign currency translation adjustments		28	(36)	136	(346)
Net actuarial gains (losses)			156		(22)
Other comprehensive income, net of tax		6,156	3,368	36,668	83,950
AOCI, Net of Tax, ending balance		$ 24,273	$ 65,473	$ 24,273	$ 65,473

[1] Included in net gains (losses) on investments and other financial instruments on our consolidated statements of operations.