Investments in Unconsolidated Affiliates (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	$ 2,449.8		$ 2,429.2
Equity in income (loss) of unconsolidated affiliates by business segment [Abstract]
Equity in income (loss) of unconsolidated affiliates	148.9	$ 140.8
NGL Pipelines & Services [Member]
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	664.6		671.6
Equity in income (loss) of unconsolidated affiliates by business segment [Abstract]
Equity in income (loss) of unconsolidated affiliates	28.1	32.7
Crude Oil Pipelines & Services [Member]
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	1,749.5		1,723.7
Equity in income (loss) of unconsolidated affiliates by business segment [Abstract]
Equity in income (loss) of unconsolidated affiliates	118.9	107.3
Natural Gas Pipelines & Services [Member]
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	32.5		31.4
Equity in income (loss) of unconsolidated affiliates by business segment [Abstract]
Equity in income (loss) of unconsolidated affiliates	1.4	1.6
Petrochemical & Refined Products Services [Member]
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	3.2		$ 2.5
Equity in income (loss) of unconsolidated affiliates by business segment [Abstract]
Equity in income (loss) of unconsolidated affiliates	$ 0.5	$ (0.8)