Partners' Capital and Distributions (Details 4) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended												12 Months Ended			0 Months Ended	12 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	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Feb. 14, 2014 Subsequent Event Fourth Quarter Distribution	Dec. 31, 2013 Subsequent Event Fourth Quarter Distribution
Incentive Distribution Made to Managing Member or General Partner
Cash distributions paid to common unit holders													$ 791	$ 684	$ 575	$ 221
Cash distribution paid to General Partner - Incentive													353	271	204	102
Cash distributions paid to General Partner - 2%													16	14	12	5
Total distributions paid during the period													$ 1,160	$ 969	$ 791	$ 328
Cash distributions per limited partner unit (in dollars per unit)	$ 0.6000	$ 0.5875	$ 0.5750	$ 0.5625	$ 0.5425	$ 0.5325	$ 0.5225	$ 0.5125	$ 0.4975	$ 0.4913	$ 0.4850	$ 0.4788	$ 2.3250	$ 2.1100	$ 1.95	$ 0.6150
Distribution declared, date																	Jan. 09, 2014
Unitholders of record, date																	Jan. 31, 2014