Acquisitions (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Feb. 28, 2011 Non-controlling Owners' Interest [Member] Magellan Crude Oil LLC [Member]	Jun. 30, 2011 2nd Quarter 2011 Asset Acquisitions [Member]	Apr. 30, 2011 Reagan Texas [Member]
Acquisition of interest	$ 40.5	$ 17.8
Length of petroleum products pipeline, miles			38

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