Derivative Instruments Outstanding Trading Contracts (Details) (Forward Contracts [Member])	Jun. 30, 2014 gal
Sales [Member]
Derivative [Line Items]
Quantity In Gallons	630,000
Weighted Average Contract Prices	1.1400
Sales [Member] | Maximum [Member]
Derivative [Line Items]
Estimated Market Prices	1.1400
Purchase [Member]
Derivative [Line Items]
Quantity In Gallons	631,000
Weighted Average Contract Prices	1.1302
Purchase [Member] | Maximum [Member]
Derivative [Line Items]
Estimated Market Prices	1.3176
Purchase [Member] | Minimum [Member]
Derivative [Line Items]
Estimated Market Prices	1.1300