Intangible Assets (Schedule Of Components Of Intangible Assets) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	$ 235,555	$ 236,819
Intangible assets, Accumulated Amortization	159,641	153,888
Intangible assets, Carrying Value	75,914	82,931
Refinery Services Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	94,654	94,654
Intangible assets, Accumulated Amortization	84,083	81,880
Intangible assets, Carrying Value	10,571	12,774
Refinery Services Licensing Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	38,678	38,678
Intangible assets, Accumulated Amortization	30,339	28,983
Intangible assets, Carrying Value	8,339	9,695
Refinery Services Segment Total [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	133,332	133,332
Intangible assets, Accumulated Amortization	114,422	110,863
Intangible assets, Carrying Value	18,910	22,469
Supply And Logistics Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	35,430	35,430
Intangible assets, Accumulated Amortization	31,082	30,228
Intangible assets, Carrying Value	4,348	5,202
Supply And Logistics Intangibles Associated With Lease [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	13,260	13,260
Intangible assets, Accumulated Amortization	3,749	3,512
Intangible assets, Carrying Value	9,511	9,748
Supply And Logistics Segment Total [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	48,690	48,690
Intangible assets, Accumulated Amortization	34,831	33,740
Intangible assets, Carrying Value	13,859	14,950
Marine Transportation Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	32,000	32,000
Intangible assets, Accumulated Amortization	3,333	833
Intangible assets, Carrying Value	28,667	31,167
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross Carrying Amount	21,533	22,797
Intangible assets, Accumulated Amortization	7,055	8,452
Intangible assets, Carrying Value	$ 14,478	$ 14,345