Inventories (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Inventory by Product Type [Abstract]
NGLs		$ 1,678.1		$ 1,678.1		$ 1,094.9
Petrochemicals and refined products		800.8		800.8		311.5
Crude oil		696.1		696.1		674.2
Natural gas		17.6		17.6		10.8
Total		3,192.6		3,192.6		$ 2,091.4
Summary of cost of sales and lower of cost or net realizable value adjustments [Abstract]
Cost of sales	[1]	4,313.7	$ 5,276.5	12,331.9	$ 16,721.5
Lower of cost or net realizable value adjustments recognized in cost of sales		$ 4.4	$ 6.8	$ 55.6	$ 17.1

[1] Cost of sales is a component of “Operating costs and expenses” as presented on our Unaudited Condensed Statements of Consolidated Operations.  Fluctuations in these amounts are primarily due to changes in energy commodity prices and sales volumes associated with our marketing activities.