Quarterly report pursuant to Section 13 or 15(d)

Financial Instruments - Derivatives Gross Presentation on Condsolidated Balance Sheet (Details)

v2.4.0.6
Financial Instruments - Derivatives Gross Presentation on Condsolidated Balance Sheet (Details) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2013
Dec. 31, 2012
Derivative [Line Items]    
Derivative, Collateral, Right to Reclaim Cash $ 6,400 $ 5,900
Fuel Derivatives [Member]
    
Derivative [Line Items]    
Derivative Asset, Fair Value, Gross Asset 420  
Derivative Asset, Fair Value, Amount Offset Against Collateral 0  
Derivative Asset, Fair Value, Net 420  
Derivative, Fair Value, Gross Amount Not Offset Against Collateral, Net 0 0
Derivative Liability, Fair Value, Amount Offset Against Collateral   (98)
Derivative Liability, Fair Value, Net   0
Derivative, Collateral, Right to Reclaim Cash 0 0
Derivative Liability, Fair Value, Gross Liability   (98)
LNG Inventory Derivatives [Member]
    
Derivative [Line Items]    
Derivative Asset, Fair Value, Gross Asset   237
Derivative Asset, Fair Value, Amount Offset Against Collateral   0
Derivative Asset, Fair Value, Net   237
Derivative, Fair Value, Gross Amount Not Offset Against Collateral, Net 0 0
Derivative Liability, Fair Value, Amount Offset Against Collateral (420)  
Derivative Liability, Fair Value, Net 0  
Derivative, Collateral, Right to Reclaim Cash 0 0
Derivative Liability, Fair Value, Gross Liability (420)  
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Contract [Member]
    
Derivative [Line Items]    
Derivative Liability, Fair Value, Net   (26,424)
Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]
    
Derivative [Line Items]    
Derivative, Fair Value, Gross Amount Not Offset Against Collateral, Net   0
Derivative Liability, Fair Value, Amount Offset Against Collateral   0
Derivative Liability, Fair Value, Net   (21,290)
Derivative, Collateral, Right to Reclaim Cash   0
Derivative Liability, Fair Value, Gross Liability   (21,290)
Not Designated as Hedging Instrument [Member] | Interest Rate Contract [Member]
    
Derivative [Line Items]    
Derivative, Fair Value, Gross Amount Not Offset Against Collateral, Net 0 0
Derivative Liability, Fair Value, Amount Offset Against Collateral 0 0
Derivative Liability, Fair Value, Net (23,055) (5,134)
Derivative, Collateral, Right to Reclaim Cash 0 0
Derivative Liability, Fair Value, Gross Liability (23,055) (5,134)
Not Designated as Hedging Instrument [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Contract [Member]
    
Derivative [Line Items]    
Derivative Liability, Fair Value, Net $ (23,055)