Note 5 - Fair Value of Financial Instruments (Details) - Financial Assets and Liabilities at Fair Value (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Jun. 30, 2014
Current assets:
Cost or Amortized Cost	$ 57,354		$ 80,120
Fair Value	40,015		40,991
Derivatives:
Fair Value	39,474		38,816
Forward Contracts [Member] | Fair Value, Inputs, Level 1 [Member]
Derivatives:
Fair Value		[1]		[1]
Forward Contracts [Member] | Fair Value, Inputs, Level 2 [Member]
Derivatives:
Fair Value	2,290	[1]	354	[1]
Forward Contracts [Member] | Fair Value, Inputs, Level 3 [Member]
Derivatives:
Fair Value		[1]		[1]
Forward Contracts [Member]
Derivatives:
Fair Value	2,290	[1]	354	[1]
Forward Contracts [Member] | Portion at Other than Fair Value Measurement [Member]
Derivatives:
Cost or Amortized Cost	2,290	[1]	354	[1]
Natural Gas Price Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Current liabilities:
Fair Value				[2]
Natural Gas Price Swap [Member] | Fair Value, Inputs, Level 2 [Member]
Current liabilities:
Fair Value			(2,423)	[2]
Natural Gas Price Swap [Member] | Fair Value, Inputs, Level 3 [Member]
Current liabilities:
Fair Value				[2]
Natural Gas Price Swap [Member]
Current liabilities:
Fair Value			(2,423)	[2]
Natural Gas Price Swap [Member] | Portion at Other than Fair Value Measurement [Member]
Current liabilities:
Cost or Amortized Cost			(2,423)	[2]
Crude Oil Price Swap [Member] | Fair Value, Inputs, Level 1 [Member]
Current liabilities:
Fair Value		[3]		[3]
Crude Oil Price Swap [Member] | Fair Value, Inputs, Level 2 [Member]
Current liabilities:
Fair Value	(2,490)	[3]	(106)	[3]
Crude Oil Price Swap [Member] | Fair Value, Inputs, Level 3 [Member]
Current liabilities:
Fair Value		[3]		[3]
Crude Oil Price Swap [Member]
Current liabilities:
Fair Value	(2,490)	[3]	(106)	[3]
Crude Oil Price Swap [Member] | Portion at Other than Fair Value Measurement [Member]
Current liabilities:
Cost or Amortized Cost	(2,490)	[3]	(106)	[3]
Fair Value, Inputs, Level 1 [Member] | Natural Gas Price Swap [Member]
Current liabilities:
Fair Value		[2]
Fair Value, Inputs, Level 1 [Member]
Current assets:
Fair Value	40,015		40,991
Derivatives:
Fair Value	40,015		40,991
Fair Value, Inputs, Level 2 [Member] | Natural Gas Price Swap [Member]
Current liabilities:
Fair Value	(341)	[2]
Fair Value, Inputs, Level 2 [Member]
Derivatives:
Fair Value	(541)		(2,175)
Fair Value, Inputs, Level 3 [Member] | Natural Gas Price Swap [Member]
Current liabilities:
Fair Value		[2]
Natural Gas Price Swap [Member]
Current liabilities:
Fair Value	(341)	[2]
Natural Gas Price Swap [Member] | Portion at Other than Fair Value Measurement [Member]
Current liabilities:
Cost or Amortized Cost	(341)	[2]
Portion at Other than Fair Value Measurement [Member]
Current assets:
Cost or Amortized Cost	40,015		40,991
Derivatives:
Cost or Amortized Cost	39,474		38,816
Current liabilities:
	$ 312,013

[1] This amount relates to derivatives which represent currency forward contracts, valued primarily based on observable inputs, including forward and spot prices for currencies, netted against contracted rates and then multiplied against notational amounts, and are included within "prepaid expenses and other" in the condensed consolidated balance sheet with the corresponding gain or loss being recognized within "foreign currency translation and transaction gains (losses)" in the condensed consolidated statement of operations andcomprehensive income (loss).

[2] This amount relates to derivatives which represent swap contracts on natural gas prices, valued primarily based on observable inputs, including forward and spot prices for related commodity indices, and are included within "prepaid expenses and other" and "accounts payable and accrued expenses" in the condensed consolidated balance sheet with the corresponding gain or loss being recognized within "electricity revenues" in the condensed consolidated statement of operations and comprehensive income (loss).

[3] This amount relates to derivatives which represent swap contracts on oil prices, valued primarily based on observable inputs, including forward and spot prices for related commodity indices, and are included within "prepaid expenses and other" and "accounts payable and accrued expenses" in the condensed consolidated balance sheet with the corresponding gain or loss being recognized within "electricity revenues" in the condensed consolidated statement of operations and comprehensive income (loss).