Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Consolidated Revenues [Abstract]
Total consolidated revenues	$ 8,426.6	$ 6,886.9	$ 6,607.6	$ 7,320.4	$ 6,478.8	$ 5,920.4	$ 5,617.8	$ 5,005.3	$ 29,241.5	$ 23,022.3	$ 27,027.9
NGL Pipelines & Services [Member]
Consolidated Revenues [Abstract]
Sales of NGLs and related products									10,521.3	8,380.5	8,044.8
Midstream services									1,946.7	1,862.0	1,743.2
Total consolidated revenues									12,468.0	10,242.5	9,788.0
Crude Oil Pipelines & Services [Member]
Consolidated Revenues [Abstract]
Sales of crude oil									7,365.2	5,802.5	9,732.9
Midstream services									791.6	712.5	573.0
Total consolidated revenues									8,156.8	6,515.0	10,305.9
Natural Gas Pipelines & Services [Member]
Consolidated Revenues [Abstract]
Sales of natural gas									2,238.5	1,591.9	1,722.6
Midstream services									907.1	951.1	1,020.7
Total consolidated revenues									3,145.6	2,543.0	2,743.3
Petrochemical & Refined Products Services [Member]
Consolidated Revenues [Abstract]
Sales of petrochemicals and refined products									4,696.3	2,921.9	3,333.5
Midstream services									774.8	799.9	778.4
Total consolidated revenues									5,471.1	3,721.8	4,111.9
Offshore Pipelines And Services [Member]
Consolidated Revenues [Abstract]
Sales of crude oil									0.0	0.0	3.2
Midstream services									0.0	0.0	75.6
Total consolidated revenues									$ 0.0	$ 0.0	$ 78.8