Derivative Financial Instruments (Schedule Of Derivative Obligations Under Terminated Hedge Arrangements) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Derivative [Line Items]
Derivative losses, net	$ (104)	$ (42)
Commodity Price Derivatives [Member] | Derivative Gains, Net [Member]
Derivative [Line Items]
Derivative losses, net	(114)	(46)
Interest Rate Derivatives [Member] | Derivative Gains, Net [Member]
Derivative [Line Items]
Derivative losses, net	$ 10	$ 4