Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments and Hedging Activities (Potential Impact of Rights of Offset Associated with Recognized Assets and Liabilities) (Details)

v2.4.0.8
Derivative Instruments and Hedging Activities (Potential Impact of Rights of Offset Associated with Recognized Assets and Liabilities) (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2013
Dec. 31, 2012
Offsetting Assets and Liabilities [Line Items]    
Derivative Assets, Current $ 0 $ 1,674
Current assets: Fair value of hedging contracts [Member] | Hedging Contracts [Member]
    
Offsetting Assets and Liabilities [Line Items]    
Derivative Asset, Fair Value, Gross Asset 96  
Derivative Asset, Collateral, Obligation to Return Cash, Offset (96)  
Derivative Asset, Fair Value, Amount Offset Against Collateral 0  
Long-term assets: Fair value of hedging contracts [Member] | Hedging Contracts [Member]
    
Offsetting Assets and Liabilities [Line Items]    
Derivative Asset, Fair Value, Gross Asset 155  
Derivative Asset, Collateral, Obligation to Return Cash, Offset (119)  
Derivative Asset, Fair Value, Amount Offset Against Collateral 36  
Current liabilities: Fair value of hedging contracts [Member] | Hedging Contracts [Member]
    
Offsetting Assets and Liabilities [Line Items]    
Derivative Liability, Fair Value, Gross Liability (1,235)  
Derivative Liability, Collateral, Right to Reclaim Cash, Offset 96  
Derivative Liability, Fair Value, Amount Offset Against Collateral (1,139)  
Long-term liabilities: Fair value of hedging contracts [Member] | Hedging Contracts [Member]
    
Offsetting Assets and Liabilities [Line Items]    
Derivative Liability, Fair Value, Gross Liability (137)  
Derivative Liability, Collateral, Right to Reclaim Cash, Offset 119  
Derivative Liability, Fair Value, Amount Offset Against Collateral $ (18)