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, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Concentration Risk
Concentration Risk, Percentage									10.00%
Major customer, revenue amount	$ 677	$ 665	$ 639	$ 540	$ 587	$ 527	$ 511	$ 375	$ 2,521	$ 2,000	$ 1,434
Gathering And Processing
Concentration Risk
Major customer, revenue amount									2,287	1,797	1,226
Gathering And Processing | Customer A
Concentration Risk
Major customer, revenue amount									381	367	366
Gathering And Processing | Customer B [Member]
Concentration Risk
Major customer, revenue amount									362	451	0
Gathering And Processing | Supplier A
Concentration Risk
Major supplier, cost of sales amount									164	171	133
Gathering And Processing | Supplier B [Member]
Concentration Risk
Major supplier, cost of sales amount									$ 185	$ 0	$ 0