Related Party Transactions (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenues:
Terminalling and storage	$ 19,045	$ 18,044	$ 55,798	$ 52,857
Marine transportation	6,076	5,943	18,340	18,828
Product sales:
Product Sales Related Party	883	964	6,484	4,012
Cost of products sold:
Natural gas services	9,908	7,799	29,169	23,391
Sulfur services	4,491	4,539	13,808	13,514
Terminalling and storage	9,174	13,488	25,571	39,638
Operating Expenses:
Operating expenses	21,013	17,902	58,500	53,410
Related Party [Member]
Product sales:
Product Sales Related Party	883	964	6,484	4,012
Revenue from Related Parties	26,004	24,951	80,622	75,697
Cost of products sold:
Terminalling and storage	23,573	25,826	68,548	76,543
Operating Expenses:
Operating expenses	21,013	17,902	58,500	53,410
Selling, general and administrative:
Selling, general and administrative	7,230	4,356	18,103	12,944
Related Party [Member] | Marine transportation [Member]
Operating Expenses:
Operating expenses	10,198	9,697	28,685	29,260
Selling, general and administrative:
Selling, general and administrative	8	15	23	45
Related Party [Member] | Natural gas services [Member]
Product sales:
Product Sales Related Party	0	0	3,046	9
Operating Expenses:
Operating expenses	1,510	542	2,914	1,496
Selling, general and administrative:
Selling, general and administrative	2,647	635	4,751	1,623
Related Party [Member] | Sulfur services [Member]
Product sales:
Product Sales Related Party	708	809	2,931	3,460
Operating Expenses:
Operating expenses	2,121	2,115	5,641	6,405
Selling, general and administrative:
Selling, general and administrative	840	748	2,503	2,360
Related Party [Member] | Terminalling and storage [Member]
Product sales:
Product Sales Related Party	175	155	507	543
Operating Expenses:
Operating expenses	7,184	5,548	21,260	16,249
Selling, general and administrative:
Selling, general and administrative	317	291	1,045	935
Related Party [Member] | Indirect overhead allocation, net of reimbursement [Member]
Selling, general and administrative:
Selling, general and administrative	$ 3,418	$ 2,667	$ 9,781	$ 7,981