Inventories (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Available-for-Sale Inventory by Product Type [Abstract]
NGLs	$ 593.8		$ 594.3
Petrochemicals and refined products	395.1		304.5
Crude oil	42.6		119.4
Natural gas	61.6		70.2
Total	1,093.1		1,088.4
Summary of cost of sales and lower of cost or market adjustments [Abstract]
Cost of sales	40,770.2	[1]	36,015.5	[1]	38,292.6	[1]
Lower of cost or market adjustments	$ 18.5		$ 22.1		$ 9.5

[1] Cost of sales is a component of "Operating costs and expenses," as presented on our Statements of Consolidated Operations. Year-to-year fluctuations in these amounts are primarily due to changes in energy commodity prices and sales volumes associated with our marketing activities.