Note 6 - Investments Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net Investment Income [Line Items]
Gross Investment Income, Operating	$ 120,213	$ 87,011	$ 70,733
Investment Income, Investment Expense	(6,747)	(5,474)	(5,078)
Investment Income, Net	113,466	81,537	65,655
Fixed Maturities [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	115,880	81,127	62,352
Equity securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	86	4,539	6,287
Short-term Investments [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	3,086	745	246
Other Security Investments [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	$ 1,161	$ 600	$ 1,848

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a),(b))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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