Concentration Risk Table - Schedule Of Revenues And Cost Of Sales By Major Customer And Supplier (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Concentration Risk
Concentration Risk, Percentage									10.00%
Major customer, revenue amount	$ 1,427	$ 1,483	$ 1,178	$ 863	$ 677	$ 665	$ 639	$ 540	$ 4,951	$ 2,521	$ 2,000
Gathering And Processing
Concentration Risk
Major customer, revenue amount									4,570	2,287	1,797
Gathering And Processing | Customer A
Concentration Risk
Major customer, revenue amount									0	381	367
Gathering And Processing | Customer B [Member]
Concentration Risk
Major customer, revenue amount									780	362	451
Gathering And Processing | Supplier A
Concentration Risk
Major supplier, cost of sales amount									0	164	171
Gathering And Processing | Supplier B [Member]
Concentration Risk
Major supplier, cost of sales amount									$ 0	$ 185	$ 0