v3.25.3
Business Segment Information (Schedule of Segment Information) (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Segment Reporting Information [Line Items]        
Revenues $ 414,001,000 $ 397,291,000 $ 1,189,660,000 $ 1,261,917,000
Total Segment Margin 146,576,000 121,979,000 403,840,000 407,162,000
Offshore pipeline transportation        
Segment Reporting Information [Line Items]        
Revenues 143,306,000 101,119,000 377,563,000 302,133,000
Marine transportation        
Segment Reporting Information [Line Items]        
Revenues 77,058,000 78,496,000 237,319,000 243,941,000
Onshore transportation and services        
Segment Reporting Information [Line Items]        
Revenues 193,637,000 217,676,000 574,778,000 715,843,000
Operating Segments        
Segment Reporting Information [Line Items]        
Revenues 414,001,000   1,189,660,000  
Segment Operating Expenses (148,217,000) (140,905,000) (446,556,000) (444,597,000)
Segment Product Costs (114,837,000) (137,440,000) (335,007,000) (456,983,000)
Other Segment Items (4,371,000) 3,033,000 (4,257,000) 46,825,000
Total Segment Margin 146,576,000 121,979,000 403,840,000 407,162,000
Operating Segments | Offshore pipeline transportation        
Segment Reporting Information [Line Items]        
Revenues 143,250,000   377,265,000  
Segment Operating Expenses (36,414,000) (30,303,000) (105,329,000) (88,013,000)
Segment Product Costs 0 0 0 0
Other Segment Items (5,549,000) 1,333,000 (6,749,000) 41,966,000
Total Segment Margin 101,343,000 72,149,000 265,485,000 256,086,000
Operating Segments | Marine transportation        
Segment Reporting Information [Line Items]        
Revenues 77,058,000   237,319,000  
Segment Operating Expenses (51,738,000) (47,219,000) (152,604,000) (150,229,000)
Segment Product Costs 0 0 0 0
Other Segment Items 250,000 (209,000) 693,000 262,000
Total Segment Margin 25,570,000 31,068,000 85,408,000 93,974,000
Operating Segments | Onshore transportation and services        
Segment Reporting Information [Line Items]        
Revenues 193,693,000   575,076,000  
Operating Segments | Onshore transportation and services        
Segment Reporting Information [Line Items]        
Segment Operating Expenses (60,065,000) (63,383,000) (188,623,000) (206,355,000)
Segment Product Costs (114,837,000) (137,440,000) (335,007,000) (456,983,000)
Other Segment Items 928,000 1,909,000 1,799,000 4,597,000
Total Segment Margin 19,663,000 $ 18,762,000 52,947,000 $ 57,102,000
Intersegment        
Segment Reporting Information [Line Items]        
Revenues 0   0  
Intersegment | Offshore pipeline transportation        
Segment Reporting Information [Line Items]        
Revenues 56,000   298,000  
Intersegment | Marine transportation        
Segment Reporting Information [Line Items]        
Revenues 0   0  
Intersegment | Onshore transportation and services        
Segment Reporting Information [Line Items]        
Revenues $ (56,000)   $ (298,000)