Business Segments, Segment Reporting Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Information by business segment [Abstract]
Segment gross operating margin	$ 2,002.9	$ 2,086.2	$ 4,060.1	$ 4,214.6
Mark-to-market gains (losses) in gross operating margin	61.9	(12.5)	91.4	83.8
Revenues from third parties	5,745.3	8,250.5	13,211.8	16,781.7
Revenues from related parties	5.7	25.8	21.7	38.1
Intersegment and intrasegment revenues	0.0	0.0	0.0	0.0
Total revenues	5,751.0	8,276.3	13,233.5	16,819.8
Equity in income (loss) of unconsolidated affiliates	113.3	137.4	254.1	292.0
Property, plant and equipment, net	42,538.4		42,538.4		$ 41,603.4
Investments in unconsolidated affiliates	2,547.4		2,547.4		2,600.2
Intangible assets, net	3,379.4		3,379.4		3,449.0
Goodwill	5,745.2		5,745.2		5,745.2
Segment assets	54,210.4		54,210.4		53,397.8
NGL Pipelines & Services [Member]
Information by business segment [Abstract]
Total revenues	2,476.3	3,284.7	5,444.4	6,599.1
Equity in income (loss) of unconsolidated affiliates	28.8	26.7	61.5	56.8
Investments in unconsolidated affiliates	685.9		685.9		703.8
Intangible assets, net	347.4		347.4		360.2
Crude Oil Pipelines & Services [Member]
Information by business segment [Abstract]
Total revenues	1,463.2	2,866.6	3,502.1	5,473.9
Equity in income (loss) of unconsolidated affiliates	84.1	111.0	191.4	235.6
Investments in unconsolidated affiliates	1,828.7		1,828.7		1,866.5
Intangible assets, net	1,968.8		1,968.8		2,001.9
Natural Gas Pipelines & Services [Member]
Information by business segment [Abstract]
Total revenues	585.2	819.3	1,255.8	1,746.8
Equity in income (loss) of unconsolidated affiliates	1.3	1.6	2.9	3.3
Investments in unconsolidated affiliates	28.5		28.5		27.3
Intangible assets, net	921.4		921.4		941.2
Petrochemical & Refined Products Services [Member]
Information by business segment [Abstract]
Total revenues	1,226.3	1,305.7	3,031.2	3,000.0
Equity in income (loss) of unconsolidated affiliates	(0.9)	(1.9)	(1.7)	(3.7)
Investments in unconsolidated affiliates	4.3		4.3		2.6
Intangible assets, net	141.8		141.8		145.7
Reportable Business Segments [Member] | NGL Pipelines & Services [Member]
Information by business segment [Abstract]
Segment gross operating margin	968.1	966.3	2,010.1	1,925.5
Mark-to-market gains (losses) in gross operating margin	35.7	(0.7)	23.4	0.6
Revenues from third parties	2,474.7	3,282.2	5,441.0	6,593.8
Revenues from related parties	1.6	2.5	3.4	5.3
Intersegment and intrasegment revenues	5,947.7	4,494.8	11,728.4	9,986.2
Total revenues	8,424.0	7,779.5	17,172.8	16,585.3
Equity in income (loss) of unconsolidated affiliates	28.8	26.7	61.5	56.8
Property, plant and equipment, net	16,885.9		16,885.9		16,652.1
Investments in unconsolidated affiliates	685.9		685.9		703.8
Intangible assets, net	347.4		347.4		360.2
Goodwill	2,651.7		2,651.7		2,651.7
Segment assets	20,570.9		20,570.9		20,367.8
Reportable Business Segments [Member] | Crude Oil Pipelines & Services [Member]
Information by business segment [Abstract]
Segment gross operating margin	634.4	513.2	1,087.3	1,175.5
Mark-to-market gains (losses) in gross operating margin	8.1	(14.6)	18.8	85.2
Revenues from third parties	1,461.3	2,847.0	3,489.0	5,448.6
Revenues from related parties	1.9	19.6	13.1	25.3
Intersegment and intrasegment revenues	4,039.9	9,453.3	11,880.2	17,338.3
Total revenues	5,503.1	12,319.9	15,382.3	22,812.2
Equity in income (loss) of unconsolidated affiliates	84.1	111.0	191.4	235.6
Property, plant and equipment, net	6,412.8		6,412.8		6,324.4
Investments in unconsolidated affiliates	1,828.7		1,828.7		1,866.5
Intangible assets, net	1,968.8		1,968.8		2,001.9
Goodwill	1,841.0		1,841.0		1,841.0
Segment assets	12,051.3		12,051.3		12,033.8
Reportable Business Segments [Member] | Natural Gas Pipelines & Services [Member]
Information by business segment [Abstract]
Segment gross operating margin	208.9	301.8	492.7	566.1
Mark-to-market gains (losses) in gross operating margin	(4.0)	0.3	24.8	0.0
Revenues from third parties	583.0	815.6	1,250.6	1,739.3
Revenues from related parties	2.2	3.7	5.2	7.5
Intersegment and intrasegment revenues	92.9	163.1	208.0	358.5
Total revenues	678.1	982.4	1,463.8	2,105.3
Equity in income (loss) of unconsolidated affiliates	1.3	1.6	2.9	3.3
Property, plant and equipment, net	8,429.7		8,429.7		8,432.5
Investments in unconsolidated affiliates	28.5		28.5		27.3
Intangible assets, net	921.4		921.4		941.2
Goodwill	296.3		296.3		296.3
Segment assets	9,675.9		9,675.9		9,697.3
Reportable Business Segments [Member] | Petrochemical & Refined Products Services [Member]
Information by business segment [Abstract]
Segment gross operating margin	191.5	304.9	470.0	547.5
Mark-to-market gains (losses) in gross operating margin	22.1	2.5	24.4	(2.0)
Revenues from third parties	1,226.3	1,305.7	3,031.2	3,000.0
Revenues from related parties	0.0	0.0	0.0	0.0
Intersegment and intrasegment revenues	709.7	617.9	1,517.8	1,332.3
Total revenues	1,936.0	1,923.6	4,549.0	4,332.3
Equity in income (loss) of unconsolidated affiliates	(0.9)	(1.9)	(1.7)	(3.7)
Property, plant and equipment, net	7,530.6		7,530.6		7,553.2
Investments in unconsolidated affiliates	4.3		4.3		2.6
Intangible assets, net	141.8		141.8		145.7
Goodwill	956.2		956.2		956.2
Segment assets	8,632.9		8,632.9		8,657.7
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	(10,790.2)	(14,729.1)	(25,334.4)	(29,015.3)
Total revenues	(10,790.2)	(14,729.1)	(25,334.4)	(29,015.3)
Equity in income (loss) of unconsolidated affiliates	0.0	$ 0.0	0.0	$ 0.0
Adjustments [Member]
Information by business segment [Abstract]
Property, plant and equipment, net	3,279.4		3,279.4		2,641.2
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	$ 3,279.4		$ 3,279.4		$ 2,641.2