Price Risk Management Activities (Details) lb in Thousands, bu in Thousands, MMBTU in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) MMBTU lb MBbls bu	Sep. 30, 2014 USD ($)
Price Risk Management Activities (Textual)
Compliance program costs | $	$ 95	$ 82	$ 283	$ 265
Foreign Currency Contracts [Member]
Price Risk Management Activities (Textual)
Monetary notional amount of derivative liabilities | $	$ 344		$ 344
Foreign currency commitments maturity date			Oct. 31, 2015
Fair Value Hedging [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			0
Cash Flow Hedging [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			0
Economic Hedging [Member] | Swap, Maturity Current Year [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			11,605
Economic Hedging [Member] | Swap, Maturity Current Year [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			11,519
Economic Hedging [Member] | Swap, Maturity Year Two [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			700
Economic Hedging [Member] | Swap, Maturity Year Two [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			330
Economic Hedging [Member] | Swap, Maturity Year Three [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			0
Economic Hedging [Member] | Swap, Maturity Year Three [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			0
Economic Hedging [Member] | Future, Maturity Current Year [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			49,472
Economic Hedging [Member] | Future, Maturity Current Year [Member] | Long (Purchases) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			13,615
Economic Hedging [Member] | Future, Maturity Current Year [Member] | Long (Purchases) [Member] | Soybean Oil (in pounds) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, pounds | lb			28,980
Economic Hedging [Member] | Future, Maturity Current Year [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			57,858
Economic Hedging [Member] | Future, Maturity Current Year [Member] | Short (Sales) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			24,450
Economic Hedging [Member] | Future, Maturity Current Year [Member] | Short (Sales) [Member] | Soybean Oil (in pounds) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, pounds | lb			77,220
Economic Hedging [Member] | Future, Maturity Year Two [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			2,327
Economic Hedging [Member] | Future, Maturity Year Two [Member] | Long (Purchases) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			85
Economic Hedging [Member] | Future, Maturity Year Two [Member] | Long (Purchases) [Member] | Soybean Oil (in pounds) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, pounds | lb			900
Economic Hedging [Member] | Future, Maturity Year Two [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			4,109
Economic Hedging [Member] | Future, Maturity Year Two [Member] | Short (Sales) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			8,555
Economic Hedging [Member] | Future, Maturity Year Two [Member] | Short (Sales) [Member] | Soybean Oil (in pounds) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, pounds | lb			28,560
Economic Hedging [Member] | Future, Maturity Year Three [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			0
Economic Hedging [Member] | Future, Maturity Year Three [Member] | Long (Purchases) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			10
Economic Hedging [Member] | Future, Maturity Year Three [Member] | Long (Purchases) [Member] | Soybean Oil (in pounds) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, pounds | lb			0
Economic Hedging [Member] | Future, Maturity Year Three [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			0
Economic Hedging [Member] | Future, Maturity Year Three [Member] | Short (Sales) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			20
Economic Hedging [Member] | Future, Maturity Year Three [Member] | Short (Sales) [Member] | Soybean Oil (in pounds) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, pounds | lb			0
Economic Hedging [Member] | Forward Contracts, Maturity Current Year [Member] | Long (Purchases) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			13,188
Economic Hedging [Member] | Forward Contracts, Maturity Year Two [Member] | Long (Purchases) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			5,520
Economic Hedging [Member] | Forward Contracts, Maturity Year Three [Member] | Long (Purchases) [Member] | Corn (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu			8
Trading Derivatives [Member] | Swap, Maturity Current Year [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			7,275
Trading Derivatives [Member] | Swap, Maturity Current Year [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			7,275
Trading Derivatives [Member] | Swap, Maturity Year Two [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			3,220
Trading Derivatives [Member] | Swap, Maturity Year Two [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			3,220
Trading Derivatives [Member] | Future, Maturity Current Year [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			43,371
Trading Derivatives [Member] | Future, Maturity Current Year [Member] | Long (Purchases) [Member] | Natural Gas (in millions of Btus) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, millions of Btus | MMBTU			2,000
Trading Derivatives [Member] | Future, Maturity Current Year [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			44,415
Trading Derivatives [Member] | Future, Maturity Year Two [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			1,982
Trading Derivatives [Member] | Future, Maturity Year Two [Member] | Long (Purchases) [Member] | Natural Gas (in millions of Btus) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, millions of Btus | MMBTU			0
Trading Derivatives [Member] | Future, Maturity Year Two [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			1,071
Trading Derivatives [Member] | Options Held, Maturity Current Year [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			11,400
Trading Derivatives [Member] | Options Held, Maturity Current Year [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			12,500
Trading Derivatives [Member] | Options Held, Maturity Year Two [Member] | Long (Purchases) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			10,500
Trading Derivatives [Member] | Options Held, Maturity Year Two [Member] | Short (Sales) [Member] | Crude Oil (in thousands of barrels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume			10,500