Inventory (Inventory) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Inventory [Line Items]
Total inventory	$ 240,167	$ 258,860
Refined Petroleum Products [Member]
Inventory [Line Items]
Total inventory	117,865	127,999
Natural Gas Liquids [Member]
Inventory [Line Items]
Total inventory	46,691	55,490
Transmix [Member]
Inventory [Line Items]
Total inventory	55,968	60,251
Crude Oil [Member]
Inventory [Line Items]
Total inventory	12,064	8,065
Additives [Member]
Inventory [Line Items]
Total inventory	$ 7,579	$ 7,055