Revenue Recognition (Disaggregated Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Total revenues	$ 518,821	$ 443,125	$ 1,543,895	$ 1,371,515
Fee-based revenues
Disaggregation of Revenue [Line Items]
Total revenues	144,798	128,211	412,930	453,505
Product Sales
Disaggregation of Revenue [Line Items]
Total revenues	347,369	296,384	1,057,149	851,242
Refinery Services
Disaggregation of Revenue [Line Items]
Total revenues	26,654	18,530	73,816	66,768
Offshore Pipeline Transportation
Disaggregation of Revenue [Line Items]
Total revenues	69,479	53,893	207,084	197,286
Offshore Pipeline Transportation | Fee-based revenues
Disaggregation of Revenue [Line Items]
Total revenues	69,479	53,893	207,084	197,286
Offshore Pipeline Transportation | Product Sales
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Offshore Pipeline Transportation | Refinery Services
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Sodium Minerals & Sulfur Services
Disaggregation of Revenue [Line Items]
Total revenues	237,651	206,731	702,025	642,745
Sodium Minerals & Sulfur Services | Fee-based revenues
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Sodium Minerals & Sulfur Services | Product Sales
Disaggregation of Revenue [Line Items]
Total revenues	210,997	188,201	628,209	575,977
Sodium Minerals & Sulfur Services | Refinery Services
Disaggregation of Revenue [Line Items]
Total revenues	26,654	18,530	73,816	66,768
Marine Transportation
Disaggregation of Revenue [Line Items]
Total revenues	48,716	51,912	136,673	170,978
Marine Transportation | Fee-based revenues
Disaggregation of Revenue [Line Items]
Total revenues	48,716	51,912	136,673	170,978
Marine Transportation | Product Sales
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Marine Transportation | Refinery Services
Disaggregation of Revenue [Line Items]
Total revenues	0	0	0	0
Onshore Facilities and Transportation
Disaggregation of Revenue [Line Items]
Total revenues	162,975	130,589	498,113	360,506
Onshore Facilities and Transportation | Fee-based revenues
Disaggregation of Revenue [Line Items]
Total revenues	26,603	22,406	69,173	85,241
Onshore Facilities and Transportation | Product Sales
Disaggregation of Revenue [Line Items]
Total revenues	136,372	108,183	428,940	275,265
Onshore Facilities and Transportation | Refinery Services
Disaggregation of Revenue [Line Items]
Total revenues	$ 0	$ 0	$ 0	$ 0