Supplemental Cash Flows Information (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash Payments [Abstract]
Interest payments, net of capitalized interest	$ 148	$ 137	$ 79
Income tax payments	128	206	70
Increase (Decrease) in Other Receivables	(9)	3	28
Non Cash Items Excluded From Statement of Cash Flows [Abstract]
(Increase) decrease in accrued capital expenditures	(75)	(124)	90
Increase in asset retirement costs	(125)	(8)	(33)
Increase (Decrease) in Other Deposits	$ 90	$ 0	$ 0