Business Segments, Segment Reporting Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Information by business segment [Abstract]
Revenues from third parties	$ 5,904.7	$ 6,294.0	$ 16,499.0	$ 20,845.6
Revenues from related parties	15.7	13.9	44.5	27.3
Intersegment and intrasegment revenues	0.0	0.0	0.0	0.0
Total revenues	5,920.4	6,307.9	16,543.5	20,872.9
Equity in income (loss) of unconsolidated affiliates	92.3	103.1	269.8	302.5
Gross operating margin	1,307.6	1,341.1	3,875.5	3,978.7
Property, plant and equipment, net	33,119.4		33,119.4		$ 32,034.7
Investments in unconsolidated affiliates	2,687.2		2,687.2		2,628.5
Intangible assets, net	3,907.2		3,907.2		4,037.2
Goodwill	5,745.2		5,745.2		5,745.2
Segment assets	45,459.0		45,459.0		44,445.6
NGL Pipelines & Services [Member]
Information by business segment [Abstract]
Total revenues	2,416.9	2,286.8	7,336.2	7,229.2
Equity in income (loss) of unconsolidated affiliates	15.9	18.9	45.0	43.0
Intangible assets, net	357.7		357.7		380.3
Goodwill	2,651.7		2,651.7		2,651.7
Crude Oil Pipelines & Services [Member]
Information by business segment [Abstract]
Total revenues	1,723.0	2,322.6	4,671.6	8,089.0
Equity in income (loss) of unconsolidated affiliates	78.4	81.2	234.3	220.5
Intangible assets, net	2,301.9		2,301.9		2,377.5
Goodwill	1,841.0		1,841.0		1,841.0
Natural Gas Pipelines & Services [Member]
Information by business segment [Abstract]
Total revenues	714.2	709.7	1,799.9	2,128.3
Equity in income (loss) of unconsolidated affiliates	1.0	0.9	2.9	2.8
Intangible assets, net	1,062.7		1,062.7		1,087.7
Goodwill	296.3		296.3		296.3
Petrochemical & Refined Products Services [Member]
Information by business segment [Abstract]
Total revenues	1,066.3	980.0	2,735.8	3,347.6
Equity in income (loss) of unconsolidated affiliates	(3.0)	(3.3)	(12.4)	(10.4)
Intangible assets, net	184.9		184.9		191.7
Goodwill	956.2		956.2		956.2
Offshore Pipelines & Services [Member]
Information by business segment [Abstract]
Total revenues	0.0	8.8	0.0	78.8
Equity in income (loss) of unconsolidated affiliates	0.0	5.4	0.0	46.6
Reportable Business Segments [Member] | NGL Pipelines & Services [Member]
Information by business segment [Abstract]
Revenues from third parties	2,414.2	2,284.6	7,328.9	7,223.2
Revenues from related parties	2.7	2.2	7.3	6.0
Intersegment and intrasegment revenues	4,772.4	2,461.0	12,828.0	7,685.1
Total revenues	7,189.3	4,747.8	20,164.2	14,914.3
Equity in income (loss) of unconsolidated affiliates	15.9	18.9	45.0	43.0
Gross operating margin	703.5	695.5	2,206.3	2,041.3
Property, plant and equipment, net	14,040.1		14,040.1		12,909.7
Investments in unconsolidated affiliates	747.5		747.5		718.7
Intangible assets, net	357.7		357.7		380.3
Goodwill	2,651.7		2,651.7		2,651.7
Segment assets	17,797.0		17,797.0		16,660.4
Reportable Business Segments [Member] | Crude Oil Pipelines & Services [Member]
Information by business segment [Abstract]
Revenues from third parties	1,712.9	2,316.4	4,641.8	8,080.4
Revenues from related parties	10.1	6.2	29.8	8.6
Intersegment and intrasegment revenues	2,445.2	1,142.1	6,390.3	3,958.9
Total revenues	4,168.2	3,464.7	11,061.9	12,047.9
Equity in income (loss) of unconsolidated affiliates	78.4	81.2	234.3	220.5
Gross operating margin	254.0	254.6	633.7	704.2
Property, plant and equipment, net	4,074.1		4,074.1		3,550.3
Investments in unconsolidated affiliates	1,838.7		1,838.7		1,813.4
Intangible assets, net	2,301.9		2,301.9		2,377.5
Goodwill	1,841.0		1,841.0		1,841.0
Segment assets	10,055.7		10,055.7		9,582.2
Reportable Business Segments [Member] | Natural Gas Pipelines & Services [Member]
Information by business segment [Abstract]
Revenues from third parties	711.3	705.2	1,792.5	2,117.5
Revenues from related parties	2.9	4.5	7.4	10.8
Intersegment and intrasegment revenues	201.2	180.2	472.8	519.7
Total revenues	915.4	889.9	2,272.7	2,648.0
Equity in income (loss) of unconsolidated affiliates	1.0	0.9	2.9	2.8
Gross operating margin	178.5	192.4	533.6	588.3
Property, plant and equipment, net	8,473.7		8,473.7		8,620.0
Investments in unconsolidated affiliates	22.0		22.0		22.5
Intangible assets, net	1,062.7		1,062.7		1,087.7
Goodwill	296.3		296.3		296.3
Segment assets	9,854.7		9,854.7		10,026.5
Reportable Business Segments [Member] | Petrochemical & Refined Products Services [Member]
Information by business segment [Abstract]
Revenues from third parties	1,066.3	980.0	2,735.8	3,347.6
Revenues from related parties	0.0	0.0	0.0	0.0
Intersegment and intrasegment revenues	315.4	267.3	865.8	875.8
Total revenues	1,381.7	1,247.3	3,601.6	4,223.4
Equity in income (loss) of unconsolidated affiliates	(3.0)	(3.3)	(12.4)	(10.4)
Gross operating margin	171.6	191.5	501.9	547.4
Property, plant and equipment, net	3,255.1		3,255.1		3,060.7
Investments in unconsolidated affiliates	79.0		79.0		73.9
Intangible assets, net	184.9		184.9		191.7
Goodwill	956.2		956.2		956.2
Segment assets	4,475.2		4,475.2		4,282.5
Reportable Business Segments [Member] | Offshore Pipelines & Services [Member]
Information by business segment [Abstract]
Revenues from third parties	0.0	7.8	0.0	76.9
Revenues from related parties	0.0	1.0	0.0	1.9
Intersegment and intrasegment revenues	0.0	0.1	0.0	0.6
Total revenues	0.0	8.9	0.0	79.4
Equity in income (loss) of unconsolidated affiliates	0.0	5.4	0.0	46.6
Gross operating margin	0.0	7.1	0.0	97.5
Property, plant and equipment, net	0.0		0.0		0.0
Investments in unconsolidated affiliates	0.0		0.0		0.0
Intangible assets, net	0.0		0.0		0.0
Goodwill	0.0		0.0		0.0
Segment assets	0.0		0.0		0.0
Eliminations [Member]
Information by business segment [Abstract]
Revenues from third parties	0.0	0.0	0.0	0.0
Revenues from related parties	0.0	0.0	0.0	0.0
Intersegment and intrasegment revenues	(7,734.2)	(4,050.7)	(20,556.9)	(13,040.1)
Total revenues	(7,734.2)	(4,050.7)	(20,556.9)	(13,040.1)
Equity in income (loss) of unconsolidated affiliates	0.0	0.0	0.0	0.0
Gross operating margin	0.0	$ 0.0	0.0	$ 0.0
Adjustments [Member]
Information by business segment [Abstract]
Property, plant and equipment, net	3,276.4		3,276.4		3,894.0
Investments in unconsolidated affiliates	0.0		0.0		0.0
Intangible assets, net	0.0		0.0		0.0
Goodwill	0.0		0.0		0.0
Segment assets	$ 3,276.4		$ 3,276.4		$ 3,894.0