Derivative and Hedging Activities - Derivatives Not Designated as Hedging Instruments Table (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in net income (loss)	$ (58)	$ 7	$ (14)
Not designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in net income (loss)	96	891	336
Not designated as hedging instruments | Commodity contracts | Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in net income (loss)	159	892	348
Not designated as hedging instruments | Interest rate contract | Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in net income (loss)	$ (63)	$ (1)	$ (12)