Note 4 - Fair Value of Financial Instruments Other Fair Value Disclosure (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt		$ 1,224,892	$ 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		13,600	14,600
Long-term debt		1,224,900	1,192,300
Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other invested assets fair value disclosure	[1]	21,000	20,500
Long-term Debt, Fair Value	[1]	$ 1,681,000	$ 1,859,300

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