Revenue Recognition (Contract Assets and Liabilities) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Segment Reporting Information [Line Items]
Other Assets, net of amortization	$ 1,631		$ 1,631		$ 859
Accrued Liabilities	34,378		34,378		11,460
Other Long-Term Liabilities	104,216		104,216		$ 112,734
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	756,261	$ 804,662	1,526,366	$ 1,595,274
Offshore pipeline transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	99,024	91,459	201,014	182,854
Soda and sulfur services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	389,994	462,855	790,942	907,503
Marine transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	81,871	77,343	165,445	160,569
Onshore facilities and transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	185,372	173,005	368,965	344,348
Fee-based Revenues [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	199,325	182,699	400,182	371,504
Fee-based Revenues [Member] | Offshore pipeline transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	99,024	91,459	201,014	182,854
Fee-based Revenues [Member] | Soda and sulfur services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	0	0	0	0
Fee-based Revenues [Member] | Marine transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	81,871	77,343	165,445	160,569
Fee-based Revenues [Member] | Onshore facilities and transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	18,430	13,897	33,723	28,081
Product Sales [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	536,510	599,409	1,082,871	1,179,392
Product Sales [Member] | Offshore pipeline transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	0	0	0	0
Product Sales [Member] | Soda and sulfur services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	369,568	440,301	747,629	863,125
Product Sales [Member] | Marine transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	0	0	0	0
Product Sales [Member] | Onshore facilities and transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	166,942	159,108	335,242	316,267
Refinery Services [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	20,426	22,554	43,313	44,378
Refinery Services [Member] | Offshore pipeline transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	0	0	0	0
Refinery Services [Member] | Soda and sulfur services
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	20,426	22,554	43,313	44,378
Refinery Services [Member] | Marine transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	0	0	0	0
Refinery Services [Member] | Onshore facilities and transportation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenues	$ 0	$ 0	$ 0	$ 0