v2.4.0.8
Derivative Financial Instruments (Derivatives and Hedging - Designated) (Details) (USD $)
In Thousands, unless otherwise specified
Sep. 30, 2014
Dec. 31, 2013
Designated as Hedging Instrument [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset $ 743 $ 2,235
Derivative Liability, Fair Value, Gross Liability 2,613 146
Designated as Hedging Instrument [Member] | NYMEX Commodity Contracts [Member] | Other Current Assets [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 30 0
Designated as Hedging Instrument [Member] | NYMEX Commodity Contracts [Member] | Other Current Liabilities [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Liability, Fair Value, Gross Liability 0 146
Designated as Hedging Instrument [Member] | NYMEX Commodity Contracts [Member] | Other Noncurrent Assets [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 0 2,235
Designated as Hedging Instrument [Member] | NYMEX Commodity Contracts [Member] | Other Noncurrent Liabilities [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Liability, Fair Value, Gross Liability 70 0
Designated as Hedging Instrument [Member] | Interest Rate Contract [Member] | Other Current Assets [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 713  
Designated as Hedging Instrument [Member] | Interest Rate Contract [Member] | Other Current Liabilities [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Liability, Fair Value, Gross Liability 2,543  
Not Designated as Hedging Instrument [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 31,879 430
Derivative Liability, Fair Value, Gross Liability 4,152 7,021
Not Designated as Hedging Instrument [Member] | NYMEX Commodity Contracts [Member] | Other Current Assets [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 31,879 48
Not Designated as Hedging Instrument [Member] | NYMEX Commodity Contracts [Member] | Other Current Liabilities [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Liability, Fair Value, Gross Liability 897 7,021
Not Designated as Hedging Instrument [Member] | Butane Futures Agreements [Member] | Other Current Assets [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Asset, Fair Value, Gross Asset 0 382
Not Designated as Hedging Instrument [Member] | Butane Futures Agreements [Member] | Other Current Liabilities [Member]
   
Derivatives, Fair Value [Line Items]    
Derivative Liability, Fair Value, Gross Liability $ 3,255 $ 0