Note 5 - Fair Value of Financial Instruments Other Fair Value Disclosure (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt (Note 11)	$ 1,219,454	$ 1,192,299
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other Invested Assets, Carrying Amount	1,700	14,600
Long-term debt (Note 11)	1,219,500	1,192,300
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other invested assets fair value disclosure	4,900	20,500	[1]
Long-term Debt, Fair Value	$ 1,414,900	$ 1,859,300	[1]

[1] These estimated fair values would be classified in Level II of the fair value hierarchy.