Related Party Transactions - Schedule of the Impact of Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating expenses:
Operating expenses	$ 19,440	$ 24,407	$ 41,211	$ 46,943
Related Party
Revenues:
Revenue from related parties	21,373	23,619	43,233	48,655
Cost of products sold:
Cost of products sold	6,803	10,087	15,347	18,570
Operating expenses:
Operating expenses	19,440	24,407	41,211	46,943
Selling, general and administrative:
Selling, general and administrative	8,055	8,558	16,367	17,093
Related Party \| Indirect, including overhead allocation
Selling, general and administrative:
Selling, general and administrative	4,124	4,254	8,312	8,439
Related Party \| Product sales
Revenues:
Revenue from related parties	38	286	130	707
Related Party \| Terminalling and storage
Operating expenses:
Operating expenses	4,417	4,632	8,992	9,239
Related Party \| Terminalling and storage \| Operating segments
Selling, general and administrative:
Selling, general and administrative	835	737	1,673	1,454
Related Party \| Terminalling and storage \| Terminalling and storage
Revenues:
Revenue from related parties	15,942	17,477	31,816	36,449
Related Party \| Terminalling and storage \| Terminalling and storage
Revenues:
Revenue from related parties	29	277	102	691
Cost of products sold:
Cost of products sold	4,249	7,203	10,026	13,112
Related Party \| Transportation
Operating expenses:
Operating expenses	13,388	16,319	28,941	31,299
Related Party \| Transportation \| Operating segments
Selling, general and administrative:
Selling, general and administrative	1,817	1,729	3,656	3,457
Related Party \| Transportation \| Transportation
Revenues:
Revenue from related parties	5,393	5,856	11,287	11,499
Related Party \| Natural gas liquids
Operating expenses:
Operating expenses	498	2,054	995	4,079
Related Party \| Natural gas liquids \| Operating segments
Selling, general and administrative:
Selling, general and administrative	533	1,128	1,237	2,317
Related Party \| Sulfur services
Operating expenses:
Operating expenses	1,137	1,402	2,283	2,326
Related Party \| Sulfur services \| Operating segments
Selling, general and administrative:
Selling, general and administrative	746	710	1,489	1,426
Related Party \| Sulfur services \| Sulfur services
Revenues:
Revenue from related parties	9	9	28	16
Cost of products sold:
Cost of products sold	$ 2,554	$ 2,884	$ 5,321	$ 5,458

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The portion associated with related parties of generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services during the period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

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