Supplemental Financial Statement Information (Schedule Of Balance Sheets) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Cash and cash equivalents	$ 614	$ 372	$ 293	$ 126
Accounts receivable from related companies	115	71
Other current assets	352	311
Total current assets	6,627	5,597
ADVANCES TO AND INVESTMENTS IN UNCONSOLIDATED AFFILIATES	4,708	4,737
INTANGIBLE ASSETS, net	2,266	2,291
GOODWILL	6,414	6,434
OTHER NON-CURRENT ASSETS, net	457	533
Total assets	50,140	48,904
Accounts payable	3,573	3,107
Accounts payable to related companies	18	15
Interest payable	372	334
Price risk management liabilities	106	115
Accrued and other current liabilities	1,569	1,754
Current maturities of long-term debt	611	613
Total current liabilities	6,127	5,845
LONG-TERM DEBT, less current maturities	22,343	21,440
PREFERRED UNITS OF SUBSIDIARY	73	73
OTHER NON-CURRENT LIABILITIES	938	995
COMMITMENTS AND CONTINGENCIES
General Partner	(1)	0
Limited Partners	2,047	2,125
Accumulated other comprehensive loss	(11)	(12)
Total partners’ capital	2,035	2,113
Total liabilities and equity	50,140	48,904
Parent Company [Member]
Cash and cash equivalents	42	9	57	18
Accounts receivable from related companies	4	11
Other current assets	45	3
Total current assets	91	23
ADVANCES TO AND INVESTMENTS IN UNCONSOLIDATED AFFILIATES	6,016	6,094
INTANGIBLE ASSETS, net	18	19
GOODWILL	9	9
Notes Receivable From Affiliate	166	166
OTHER NON-CURRENT ASSETS, net	53	56
Total assets	6,353	6,367
Accounts payable	1	1
Accounts payable to related companies	7	15
Interest payable	81	48
Price risk management liabilities	5	5
Accrued and other current liabilities	1	1
Current maturities of long-term debt	4	4
Total current liabilities	99	74
LONG-TERM DEBT, less current maturities	3,871	3,840
PREFERRED UNITS OF SUBSIDIARY	340	331
OTHER NON-CURRENT LIABILITIES	8	9
COMMITMENTS AND CONTINGENCIES
General Partner	(1)	0
Limited Partners	2,047	2,125
Accumulated other comprehensive loss	(11)	(12)
Total partners’ capital	2,035	2,113
Total liabilities and equity	$ 6,353	$ 6,367