Intangible Assets and Goodwill, Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Changes in carrying amount of goodwill [Roll Forward]
Balance at beginning of period	$ 5,745.2	$ 5,745.2
Impairment of goodwill	(296.3)	0.0	$ 0.0
Balance at end of period	5,448.9	5,745.2	5,745.2
NGL Pipelines & Services [Member]
Changes in carrying amount of goodwill [Roll Forward]
Balance at beginning of period	2,651.7	2,651.7
Impairment of goodwill	0.0
Balance at end of period	2,651.7	2,651.7	2,651.7
Crude Oil Pipelines & Services [Member]
Changes in carrying amount of goodwill [Roll Forward]
Balance at beginning of period	1,841.0	1,841.0
Impairment of goodwill	0.0
Balance at end of period	1,841.0	1,841.0	1,841.0
Natural Gas Pipelines & Services [Member]
Changes in carrying amount of goodwill [Roll Forward]
Balance at beginning of period	296.3	296.3
Impairment of goodwill	(296.3)
Balance at end of period	0.0	296.3	296.3
Petrochemical & Refined Products Services [Member]
Changes in carrying amount of goodwill [Roll Forward]
Balance at beginning of period	956.2	956.2
Impairment of goodwill	0.0
Balance at end of period	$ 956.2	$ 956.2	$ 956.2