Business Segments, Segment Reporting Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012	Dec. 31, 2012
Information by business segment [Abstract]
Revenues from third parties	$ 12,085.6		$ 10,461.2	$ 34,605.4		$ 31,447.1
Revenues from related parties	7.7		7.5	20.3		63.9
Revenues	12,093.3		10,468.7	34,625.7		31,511.0
Equity in income (loss) of unconsolidated affiliates	44.0		21.0	126.1		42.2
Gross operating margin	1,154.0		1,139.6	3,527.3		3,225.3
Property, plant and equipment, net (see Note 6)	26,453.9			26,453.9			24,846.4
Investments in unconsolidated affiliates (see Note 7)	2,134.5			2,134.5			1,394.6
Intangible assets, net: (see Note 8)	1,487.6			1,487.6			1,566.8
Goodwill: (see Note 8)	2,080.0	[1]		2,080.0	[1]		2,086.8	[1]
Segment assets	32,156.0			32,156.0			29,894.6
NGL Pipelines and Services [Member]
Information by business segment [Abstract]
Revenues from third parties	4,230.6		3,389.6	11,686.0		11,071.6
Revenues from related parties	0.1		2.2	0.6		7.2
Revenues	4,230.7		3,391.8	11,686.6		11,078.8
Equity in income (loss) of unconsolidated affiliates	4.1		3.0	11.8		12.0
Gross operating margin	639.6		615.8	1,777.0		1,836.5
Property, plant and equipment, net (see Note 6)	9,529.0			9,529.0			8,494.8
Investments in unconsolidated affiliates (see Note 7)	607.2			607.2			324.6
Intangible assets, net: (see Note 8)	293.9			293.9			320.6
Goodwill: (see Note 8)	341.2	[1]		341.2	[1]		341.2	[1]
Segment assets	10,771.3			10,771.3			9,481.2
Onshore Natural Gas Pipelines And Services [Member]
Information by business segment [Abstract]
Revenues from third parties	831.4		843.3	2,658.6		2,349.1
Revenues from related parties	4.1		3.2	12.1		51.4
Revenues	835.5		846.5	2,670.7		2,400.5
Equity in income (loss) of unconsolidated affiliates	1.0		0.9	2.9		3.5
Gross operating margin	213.4		183.5	601.9		565.5
Property, plant and equipment, net (see Note 6)	8,892.5			8,892.5			8,950.1
Investments in unconsolidated affiliates (see Note 7)	24.3			24.3			24.9
Intangible assets, net: (see Note 8)	1,029.9			1,029.9			1,067.9
Goodwill: (see Note 8)	296.3	[1]		296.3	[1]		296.3	[1]
Segment assets	10,243.0			10,243.0			10,339.2
Onshore Crude Oil Pipelines and Services [Member]
Information by business segment [Abstract]
Revenues from third parties	5,435.4		4,505.1	15,358.1		13,167.4
Revenues from related parties	2.1		0.1	2.1		0.1
Revenues	5,437.5		4,505.2	15,360.2		13,167.5
Equity in income (loss) of unconsolidated affiliates	34.3		16.5	101.0		20.6
Gross operating margin	146.0		117.6	579.6		252.7
Property, plant and equipment, net (see Note 6)	1,455.0			1,455.0			1,385.9
Investments in unconsolidated affiliates (see Note 7)	889.6			889.6			493.8
Intangible assets, net: (see Note 8)	4.9			4.9			5.9
Goodwill: (see Note 8)	305.1	[1]		305.1	[1]		311.2	[1]
Segment assets	2,654.6			2,654.6			2,196.8
Offshore Pipelines And Services [Member]
Information by business segment [Abstract]
Revenues from third parties	38.2		43.2	118.0		145.1
Revenues from related parties	1.4		2.0	5.5		5.2
Revenues	39.6		45.2	123.5		150.3
Equity in income (loss) of unconsolidated affiliates	9.8		6.8	24.9		17.8
Gross operating margin	37.9		40.6	118.1		131.0
Property, plant and equipment, net (see Note 6)	1,244.5			1,244.5			1,343.0
Investments in unconsolidated affiliates (see Note 7)	540.4			540.4			479.0
Intangible assets, net: (see Note 8)	57.4			57.4			66.2
Goodwill: (see Note 8)	82.1	[1]		82.1	[1]		82.1	[1]
Segment assets	1,924.4			1,924.4			1,970.3
Petrochemical and Refined Products Services [Member]
Information by business segment [Abstract]
Revenues from third parties	1,550.0		1,680.0	4,784.7		4,713.9
Revenues from related parties	0		0	0		0
Revenues	1,550.0		1,680.0	4,784.7		4,713.9
Equity in income (loss) of unconsolidated affiliates	(5.2)		(6.2)	(14.5)		(14.1)
Gross operating margin	117.1		182.1	450.7		437.2
Property, plant and equipment, net (see Note 6)	2,627.1			2,627.1			2,559.5
Investments in unconsolidated affiliates (see Note 7)	73.0			73.0			72.3
Intangible assets, net: (see Note 8)	101.5			101.5			106.2
Goodwill: (see Note 8)	1,055.3	[1]		1,055.3	[1]		1,056.0	[1]
Segment assets	3,856.9			3,856.9			3,794.0
Other Investment [Member]
Information by business segment [Abstract]
Revenues from third parties	0		0	0		0
Revenues from related parties	0		0	0		0
Equity in income (loss) of unconsolidated affiliates	0		0	0		2.4
Gross operating margin	0		0	0		2.4
Property, plant and equipment, net (see Note 6)	0			0			0
Investments in unconsolidated affiliates (see Note 7)	0			0			0
Intangible assets, net: (see Note 8)	0			0			0
Goodwill: (see Note 8)	0			0			0
Segment assets	0			0			0
Adjustments and Eliminations [Member]
Information by business segment [Abstract]
Revenues from third parties	0		0	0		0
Revenues from related parties	0		0	0		0
Equity in income (loss) of unconsolidated affiliates	0		0	0		0
Gross operating margin	0		0	0		0
Property, plant and equipment, net (see Note 6)	2,705.8			2,705.8			2,113.1
Investments in unconsolidated affiliates (see Note 7)	0			0			0
Intangible assets, net: (see Note 8)	0			0			0
Goodwill: (see Note 8)	0			0			0
Segment assets	2,705.8			2,705.8			2,113.1
Operating Segments [Member]
Information by business segment [Abstract]
Revenues	12,093.3		10,468.7	34,625.7		31,511.0
Operating Segments [Member] | NGL Pipelines and Services [Member]
Information by business segment [Abstract]
Revenues	6,773.0		5,693.4	19,318.3		18,475.1
Operating Segments [Member] | Onshore Natural Gas Pipelines And Services [Member]
Information by business segment [Abstract]
Revenues	1,051.1		1,057.9	3,397.4		3,014.6
Operating Segments [Member] | Onshore Crude Oil Pipelines and Services [Member]
Information by business segment [Abstract]
Revenues	9,028.8		6,014.4	23,693.2		18,143.1
Operating Segments [Member] | Offshore Pipelines And Services [Member]
Information by business segment [Abstract]
Revenues	41.4		45.2	131.5		155.3
Operating Segments [Member] | Petrochemical and Refined Products Services [Member]
Information by business segment [Abstract]
Revenues	1,934.4		2,158.8	5,985.4		6,071.3
Operating Segments [Member] | Other Investment [Member]
Information by business segment [Abstract]
Revenues	0		0	0		0
Operating Segments [Member] | Adjustments and Eliminations [Member]
Information by business segment [Abstract]
Revenues	(6,735.4)		(4,501.0)	(17,900.1)		(14,348.4)
Intersegment Eliminations [Member]
Information by business segment [Abstract]
Revenues	0		0	0		0
Intersegment Eliminations [Member] | NGL Pipelines and Services [Member]
Information by business segment [Abstract]
Revenues	(2,542.3)		(2,301.6)	(7,631.7)		(7,396.3)
Intersegment Eliminations [Member] | Onshore Natural Gas Pipelines And Services [Member]
Information by business segment [Abstract]
Revenues	(215.6)		(211.4)	(726.7)		(614.1)
Intersegment Eliminations [Member] | Onshore Crude Oil Pipelines and Services [Member]
Information by business segment [Abstract]
Revenues	(3,591.3)		(1,509.2)	(8,333.0)		(4,975.6)
Intersegment Eliminations [Member] | Offshore Pipelines And Services [Member]
Information by business segment [Abstract]
Revenues	(1.8)		0	(8.0)		(5.0)
Intersegment Eliminations [Member] | Petrochemical and Refined Products Services [Member]
Information by business segment [Abstract]
Revenues	(384.4)		(478.8)	(1,200.7)		(1,357.4)
Intersegment Eliminations [Member] | Other Investment [Member]
Information by business segment [Abstract]
Revenues	0		0	0		0
Intersegment Eliminations [Member] | Adjustments and Eliminations [Member]
Information by business segment [Abstract]
Revenues	$ (6,735.4)		$ (4,501.0)	$ (17,900.1)		$ (14,348.4)

[1] The total carrying amount of goodwill at September 30, 2013 and December 31, 2012 is net of $1.3 million of accumulated impairment charges. No goodwill impairment charges were recorded during the nine months ended September 30, 2013.