Derivative Instruments And Hedging Activities Notional Contracts by Derivative Type (Details)	Sep. 30, 2013 bbl	Sep. 30, 2012 bbl
Natural Gas [Member]
economic hedges by derivative type [Line Items]
Derivative, Nonmonetary Notional Amount		3,312,000
Nonmonetary Notional Amount of Price Risk Derivatives	3,312,000
Commodity WCS Spread [Member]
economic hedges by derivative type [Line Items]
Derivative, Nonmonetary Notional Amount	5,657,500	460,000
Nonmonetary Notional Amount of Price Risk Derivatives	6,117,500
Commodity WTI Long [Member]
economic hedges by derivative type [Line Items]
Derivative, Nonmonetary Notional Amount	150,000
Nonmonetary Notional Amount of Price Risk Derivatives	150,000
Commodity Gasoline [Member]
economic hedges by derivative type [Line Items]
Derivative, Nonmonetary Notional Amount	480,000	150,000
Nonmonetary Notional Amount of Price Risk Derivatives	630,000
WTI Crude Oil [Member]
economic hedges by derivative type [Line Items]
Nonmonetary Notional Amount of Price Risk Cash Flow Hedge Derivatives	13,351,000
Derivative, Nonmonetary Notional Amount	8,015,000	5,336,000
NYMEX WTI Long [Member]
economic hedges by derivative type [Line Items]
Derivative, Nonmonetary Notional Amount	234,000	0
Nonmonetary Notional Amount of Price Risk Derivatives	234,000
NYMEX WTI Short [Member]
economic hedges by derivative type [Line Items]
Derivative, Nonmonetary Notional Amount	350,000	1,856,000
Nonmonetary Notional Amount of Price Risk Derivatives	2,206,000
Ultra Low Sulfur Diesel Member
economic hedges by derivative type [Line Items]
Nonmonetary Notional Amount of Price Risk Cash Flow Hedge Derivatives	10,143,000
Derivative, Nonmonetary Notional Amount	7,475,000	2,668,000
Produced Gasoline Member
economic hedges by derivative type [Line Items]
Nonmonetary Notional Amount of Price Risk Cash Flow Hedge Derivatives	3,208,000
Derivative, Nonmonetary Notional Amount	540,000	2,668,000