Products and Services Revenues (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended		3 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 category	Dec. 31, 2012	Dec. 31, 2011 Strategic services	Dec. 31, 2013 Strategic services	Dec. 31, 2012 Strategic services	Dec. 31, 2011 Legacy services	Dec. 31, 2013 Legacy services	Dec. 31, 2012 Legacy services	Dec. 31, 2011 Affiliates and other services	Dec. 31, 2013 Affiliates and other services	Dec. 31, 2012 Affiliates and other services	Mar. 31, 2011 Predecessor	Mar. 31, 2011 Predecessor Strategic services	Mar. 31, 2011 Predecessor Legacy services	Mar. 31, 2011 Predecessor Affiliates and other services
Products and Services Revenues
Number of categories of products and services (categories)										3
Operating revenues	$ 2,207	$ 2,188	$ 2,199	$ 2,159	$ 2,210	$ 2,183	$ 2,195	$ 2,260	$ 6,635	$ 8,753	$ 8,848	$ 2,406	$ 3,342	$ 3,265	$ 2,796	$ 3,208	$ 3,471	$ 1,433	$ 2,203	$ 2,112	$ 2,268	$ 792	$ 1,003	$ 473
Taxes and surcharges included in operating revenues and expenses									$ 122	$ 154	$ 171										$ 43