Price Risk Management Activities (Details) lb in Thousands, bu in Thousands, MMBTU in Thousands, $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2017	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) MMBTU lb MBbls bu	Sep. 30, 2016 USD ($)
Price Risk Management Activities (Textual)
Compliance program costs | $		$ 230	$ 198	$ 631	$ 532
Foreign Currency Contracts [Member]
Price Risk Management Activities (Textual)
Monetary notional amount of derivative liabilities | $		$ 514		$ 514
Foreign Currency Contracts [Member] | Subsequent Event [Member]
Price Risk Management Activities (Textual)
Foreign currency commitments maturity date	Oct. 31, 2017
Economic Hedges [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				13,369
Economic Hedges [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				12,889
Economic Hedges [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				725
Economic Hedges [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				650
Economic Hedges [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 Hedges [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 Hedges [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				99,816
Economic Hedges [Member] | Future, Maturity Current Year [Member] | Long (Purchases) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				19,060
Economic Hedges [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				63,059
Economic Hedges [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				107,940
Economic Hedges [Member] | Future, Maturity Current Year [Member] | Short (Sales) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				24,985
Economic Hedges [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				157,018
Economic Hedges [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				7,014
Economic Hedges [Member] | Future, Maturity Year Two [Member] | Long (Purchases) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				20
Economic Hedges [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				0
Economic Hedges [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				6,982
Economic Hedges [Member] | Future, Maturity Year Two [Member] | Short (Sales) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				18,070
Economic Hedges [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				0
Economic Hedges [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 Hedges [Member] | Future, Maturity Year Three [Member] | Long (Purchases) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				35
Economic Hedges [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 Hedges [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 Hedges [Member] | Future, Maturity Year Three [Member] | Short (Sales) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				45
Economic Hedges [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 Hedges [Member] | Forward Contracts, Maturity Current Year [Member] | Long (Purchases) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				13,065
Economic Hedges [Member] | Forward Contracts, Maturity Year Two [Member] | Long (Purchases) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				9,223
Economic Hedges [Member] | Forward Contracts, Maturity Year Three [Member] | Long (Purchases) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				11
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				1,922
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				1,922
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				134
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				134
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				56,273
Trading Derivatives [Member] | Future, Maturity Current Year [Member] | Long (Purchases) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				400
Trading Derivatives [Member] | Future, Maturity Current Year [Member] | Long (Purchases) [Member] | Natural Gas In Btus [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, millions of Btus | MMBTU				600
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				55,234
Trading Derivatives [Member] | Future, Maturity Current Year [Member] | Short (Sales) [Member] | Natural Gas In Btus [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, millions of Btus | MMBTU				300
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				25,948
Trading Derivatives [Member] | Future, Maturity Year Two [Member] | Long (Purchases) [Member] | Grain (in bushels) [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, volume | bu				0
Trading Derivatives [Member] | Future, Maturity Year Two [Member] | Long (Purchases) [Member] | Natural Gas In 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				26,933
Trading Derivatives [Member] | Future, Maturity Year Two [Member] | Short (Sales) [Member] | Natural Gas In Btus [Member]
Volume of Outstanding Contracts
Nonmonetary notional amount of price risk derivatives, millions of Btus | MMBTU				0
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				39,380
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				38,980
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				142,450
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				142,450