Business Segments, Consolidated Revenues and Expenses (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	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, 2012		Dec. 31, 2011		Dec. 31, 2010
Consolidated Revenues [Abstract]
Total consolidated revenues	$ 11,072.1	$ 10,468.7	$ 9,789.8	$ 11,252.5	$ 11,585.7	$ 11,327.1	$ 11,216.5	$ 10,183.7	$ 42,583.1		$ 44,313.0		$ 33,739.3
Operating costs and expenses:
Cost of sales									36,015.5	[1]	38,292.6	[1]	28,723.1	[1]
Other operating costs and expenses									2,244.9	[2]	2,195.4	[2]	1,825.9	[2]
Depreciation, amortization and accretion									1,061.7		958.7		936.3
Gains attributable to disposal of assets									(17.6)		(156.0)		(44.4)
Non-cash asset impairment charges									63.4		27.8		8.4
General and administrative costs									170.3		181.8		204.8
Total costs and expenses									39,538.2		41,500.3		31,654.1
NGL Pipelines and Services [Member]
Consolidated Revenues [Abstract]
Sales of NGLs and related products									14,218.5		16,724.6		13,449.4
Midstream services									949.9		758.7		753.1
Total consolidated revenues									15,168.4		17,483.3		14,202.5
Onshore Natural Gas Pipelines And Services [Member]
Consolidated Revenues [Abstract]
Sales of natural gas									2,395.4		2,866.5		2,928.7
Midstream services									957.2		863.7		772.9
Total consolidated revenues									3,352.6		3,730.2		3,701.6
Onshore Crude Oil Pipelines and Services [Member]
Consolidated Revenues [Abstract]
Sales of crude oil									17,548.7		15,962.6		10,710.4
Midstream services									113.0		98.5		84.4
Total consolidated revenues									17,661.7		16,061.1		10,794.8
Offshore Pipelines And Services [Member]
Consolidated Revenues [Abstract]
Sales of natural gas									0.4		1.1		1.3
Sales of crude oil									3.3		9.4		9.5
Midstream services									187.8		245.5		299.9
Total consolidated revenues									191.5		256.0		310.7
Petrochemical and Refined Products Services [Member]
Consolidated Revenues [Abstract]
Sales of petrochemicals and refined products									5,470.9		6,000.6		4,009.1
Midstream services									738.0		781.8		720.6
Total consolidated revenues									$ 6,208.9		$ 6,782.4		$ 4,729.7

[1] Cost of sales is a component of "Operating costs and expenses," as presented on our Statements of Consolidated Operations. Year-to-year fluctuations in these amounts are primarily due to changes in energy commodity prices and sales volumes associated with our marketing activities.

[2] Represents cost of operating our plants, pipelines and other fixed assets, excluding non-cash depreciation, amortization and accretion charges.