Note 5 - Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014
Fair Value, Inputs, Level 1 [Member]
Fair Value of Derivatives	[1]
Fair Value, Inputs, Level 2 [Member]
Fair Value of Derivatives	[1]	$ (15,725)	$ (22,720)
Fair Value, Inputs, Level 3 [Member]
Fair Value of Derivatives	[1]
Fair Value of Derivatives	[1]	$ (15,725)	$ (22,720)

[1] Excludes cash collateral of $5.0 million provided by the Company to the counterparty at December 31, 2014. No cash collateral was provided by the Company to the counterparty at June 30, 2015.