v3.25.3
Revenue Recognition (Disaggregated Revenue) (Details) - USD ($)
 3 Months Ended 9 Months Ended
Feb. 28, 2025
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Dec. 31, 2024
Disaggregation of Revenue [Line Items]            
Total revenues   $ 414,001,000 $ 397,291,000 $ 1,189,660,000 $ 1,261,917,000  
Other Assets   7,049,000   7,049,000   $ 5,174,000
Accrued Liabilities   30,023,000   30,023,000   41,618,000
Other Long-Term Liabilities   70,161,000   70,161,000   $ 82,164,000
Proceeds from disposal of discontinued operations, net of cash divested       996,642,000 0  
Alkali Business            
Disaggregation of Revenue [Line Items]            
Proceeds from disposal of discontinued operations, net of cash divested $ 1,000,000,000          
Fee-based revenues            
Disaggregation of Revenue [Line Items]            
Total revenues   241,123,000 194,978,000 665,859,000 590,923,000  
Product sales            
Disaggregation of Revenue [Line Items]            
Total revenues   157,480,000 185,267,000 469,628,000 610,635,000  
Sulfur services            
Disaggregation of Revenue [Line Items]            
Total revenues   15,398,000 17,046,000 54,173,000 60,359,000  
Offshore pipeline transportation            
Disaggregation of Revenue [Line Items]            
Total revenues   143,306,000 101,119,000 377,563,000 302,133,000  
Offshore pipeline transportation | Fee-based revenues            
Disaggregation of Revenue [Line Items]            
Total revenues   143,306,000 101,119,000 377,563,000 302,133,000  
Offshore pipeline transportation | Product sales            
Disaggregation of Revenue [Line Items]            
Total revenues   0 0 0 0  
Offshore pipeline transportation | Sulfur services            
Disaggregation of Revenue [Line Items]            
Total revenues   0 0 0 0  
Marine transportation            
Disaggregation of Revenue [Line Items]            
Total revenues   77,058,000 78,496,000 237,319,000 243,941,000  
Marine transportation | Fee-based revenues            
Disaggregation of Revenue [Line Items]            
Total revenues   77,058,000 78,496,000 237,319,000 243,941,000  
Marine transportation | Product sales            
Disaggregation of Revenue [Line Items]            
Total revenues   0 0 0 0  
Marine transportation | Sulfur services            
Disaggregation of Revenue [Line Items]            
Total revenues   0 0 0 0  
Onshore transportation and services            
Disaggregation of Revenue [Line Items]            
Total revenues   193,637,000 217,676,000 574,778,000 715,843,000  
Onshore transportation and services | Fee-based revenues            
Disaggregation of Revenue [Line Items]            
Total revenues   20,759,000 15,363,000 50,977,000 44,849,000  
Onshore transportation and services | Product sales            
Disaggregation of Revenue [Line Items]            
Total revenues   157,480,000 185,267,000 469,628,000 610,635,000  
Onshore transportation and services | Sulfur services            
Disaggregation of Revenue [Line Items]            
Total revenues   $ 15,398,000 $ 17,046,000 $ 54,173,000 $ 60,359,000