Note 6 - Investments Change in Unrealized Gains (Losses) Recorded in AOCI (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Change In Unrealized Gains (Losses) Recorded In AOCI [Line Items]
Unrealized holding gains (losses) arising during the period, net of tax		$ 180,441	$ (97,356)	$ 31,903
Less reclassification adjustment for net gains (losses) included in net income (loss), net of tax		8,897	(10,270)	(2,642)
Net unrealized gains (losses) on investments, net of tax		171,544	(87,086)	34,545
Fixed-maturities available for sale
Change In Unrealized Gains (Losses) Recorded In AOCI [Line Items]
Unrealized holding gains (losses) arising during the period, net of tax		180,441	(97,356)	32,147
Less reclassification adjustment for net gains (losses) included in net income (loss), net of tax		8,897	(10,270)	(2,556)
Net unrealized gains (losses) on investments, net of tax		171,544	(87,086)	34,703
Equity securities
Change In Unrealized Gains (Losses) Recorded In AOCI [Line Items]
Unrealized holding gains (losses) arising during the period, net of tax	[1]	0	0	(244)
Less reclassification adjustment for net gains (losses) included in net income (loss), net of tax	[1]	0	0	(86)
Net unrealized gains (losses) on investments, net of tax	[1]	$ 0	$ 0	$ (158)

[1] Prior to our implementation of the update to the standard for the accounting of financial instruments effective January 1, 2018, the unrealized losses associated with equity securities were classified in accumulated other comprehensive income. Effective January 1, 2018, we measure our equity investments at fair value, with changes in fair value recognized in net income.