Fixed Assets And Asset Retirement Obligations (Schedule Of Fixed Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 723,225	$ 541,138
Accumulated depreciation	(157,944)	(124,213)
Net fixed assets	565,281	416,925
Pipelines And Related Assets [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	226,831	167,865
Machinery And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	87,502	46,233
Transportation Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	21,170	21,732
Marine Vessels [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	298,054	262,216
Land, Buildings And Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	15,606	13,140
Office Equipment, Furniture And Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	4,964	3,778
Construction In Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	52,541	14,236
Property, Plant And Equipment, Other Types [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 16,557	$ 11,938