v3.25.2
Note 13 - Segment and Geographic Distribution of Operations - Segment Reporting Information (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Revenue $ 341,431 $ 339,230 $ 674,875 $ 660,394  
Total vessel operating costs 167,354 176,513 332,333 344,069  
General and administrative 31,213 26,329 60,307 51,658  
Depreciation and amortization 64,314 59,445 129,746 115,715  
Additions to properties and equipment 6,855 6,392 26,219 17,334  
Total assets 2,074,372 2,089,748 2,074,372 2,089,748 $ 2,074,904
Costs of other operating revenues 3,108 816 4,538 1,966  
Corporate expenses 260,509 261,103 518,906 500,369  
Gain on asset dispositions, net 5,480 2,000 8,018 13,039  
Operating income 80,922 78,127 155,969 160,025  
Operating Segments [Member]          
Revenue 341,431 339,230 674,875 660,394  
Crew costs 99,476 106,231 196,589 208,583  
Repair and maintenance 23,937 24,743 45,891 46,091  
Insurance 1,640 2,625 4,674 5,205  
Fuel, lube and supplies 15,107 15,562 29,485 32,880  
Other 27,194 27,352 55,694 51,310  
Total vessel operating costs 167,354 176,513 332,333 344,069  
General and administrative 14,955 13,703 30,063 27,040  
Depreciation and amortization 63,391 58,682 127,874 114,206  
Operating profit 92,623 89,516 180,067 173,113  
Additions to properties and equipment 5,143 5,424 22,668 15,651  
Total assets 1,860,104 1,879,976 1,860,104 1,879,976  
Costs of other operating revenues 3,108 816 4,538 1,966  
Operating Segments [Member] | Americas [Member]          
Crew costs 19,652 23,318 37,092 47,380  
Repair and maintenance 4,830 5,645 9,096 10,179  
Insurance 351 463 922 957  
Fuel, lube and supplies 2,215 2,994 4,832 7,516  
Other 5,965 5,747 16,094 11,675  
Total vessel operating costs 33,013 38,167 68,036 77,707  
General and administrative 3,785 3,414 7,327 6,746  
Depreciation and amortization 11,718 11,413 23,110 22,356  
Operating profit 20,242 20,148 25,137 30,274  
Additions to properties and equipment 353 1,488 2,286 4,983  
Total assets 397,790 383,727 397,790 383,727  
Operating Segments [Member] | Asia Pacific [Member]          
Crew costs 18,518 23,023 38,849 42,329  
Repair and maintenance 3,365 3,092 5,635 5,861  
Insurance 176 278 500 551  
Fuel, lube and supplies 1,789 2,335 3,556 4,272  
Other 2,317 2,968 4,435 5,459  
Total vessel operating costs 26,165 31,696 52,975 58,472  
General and administrative 2,050 2,084 4,470 4,210  
Depreciation and amortization 5,703 4,510 11,021 8,542  
Operating profit 11,778 16,931 25,458 31,778  
Additions to properties and equipment 375 865 967 1,059  
Total assets 153,018 191,164 153,018 191,164  
Operating Segments [Member] | Middle East [Member]          
Crew costs 13,302 13,540 26,582 26,810  
Repair and maintenance 4,261 4,300 8,361 8,808  
Insurance 343 464 872 884  
Fuel, lube and supplies 3,250 2,274 5,289 4,578  
Other 4,661 7,138 9,249 13,144  
Total vessel operating costs 25,817 27,716 50,353 54,224  
General and administrative 2,847 2,847 5,784 5,469  
Depreciation and amortization 7,657 7,815 14,923 15,088  
Operating profit 3,894 (1,842) 12,457 (313)  
Additions to properties and equipment 329 472 1,183 1,306  
Total assets 180,769 175,129 180,769 175,129  
Operating Segments [Member] | Europe and Mediterranean [Member]          
Crew costs 29,342 27,085 56,453 53,367  
Repair and maintenance 5,736 7,058 12,447 12,551  
Insurance 417 761 1,265 1,517  
Fuel, lube and supplies 2,153 3,461 5,300 7,555  
Other 6,187 4,351 10,925 8,710  
Total vessel operating costs 43,835 42,716 86,390 83,700  
General and administrative 3,385 2,982 7,048 6,184  
Depreciation and amortization 22,833 22,439 47,442 43,877  
Operating profit 29,227 15,129 36,605 29,886  
Additions to properties and equipment 584 1,229 1,898 6,722  
Total assets 628,740 687,749 628,740 687,749  
Operating Segments [Member] | West Africa [Member]          
Crew costs 18,662 19,265 37,613 38,697  
Repair and maintenance 5,745 4,648 10,352 8,692  
Insurance 353 659 1,115 1,296  
Fuel, lube and supplies 5,700 4,498 10,508 8,959  
Other 8,064 7,148 14,991 12,322  
Total vessel operating costs 38,524 36,218 74,579 69,966  
General and administrative 2,888 2,376 5,434 4,431  
Depreciation and amortization 15,480 12,505 31,378 24,343  
Operating profit 26,017 37,739 77,630 78,749  
Additions to properties and equipment 3,502 1,370 16,334 1,581  
Total assets 499,787 442,207 499,787 442,207  
Segment Reporting, Reconciling Item, Corporate Nonsegment [Member]          
Additions to properties and equipment 1,712 968 3,551 1,683  
Total assets 214,268 209,772 214,268 209,772  
Corporate expenses (17,181) (13,389) (32,116) (26,127)  
Vessel [Member]          
Revenue 336,858 337,003 667,557 655,689  
Vessel [Member] | Operating Segments [Member]          
Revenue 336,858 337,003 667,557 655,689  
Vessel [Member] | Operating Segments [Member] | Americas [Member]          
Revenue 68,758 73,142 123,610 137,083  
Vessel [Member] | Operating Segments [Member] | Asia Pacific [Member]          
Revenue 45,696 55,221 93,924 103,002  
Vessel [Member] | Operating Segments [Member] | Middle East [Member]          
Revenue 40,215 36,536 83,517 74,468  
Vessel [Member] | Operating Segments [Member] | Europe and Mediterranean [Member]          
Revenue 99,280 83,266 177,485 163,647  
Vessel [Member] | Operating Segments [Member] | West Africa [Member]          
Revenue 82,909 88,838 189,021 177,489  
Product and Service, Other [Member]          
Revenue 4,573 2,227 7,318 4,705  
Product and Service, Other [Member] | Operating Segments [Member]          
Revenue $ 4,573 $ 2,227 $ 7,318 $ 4,705