| Fiscal period | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 |
| Period End Date | 12/31/2025 | 12/31/2024 | 12/31/2023 | 12/31/2022 | 12/31/2021 | 12/31/2020 | 12/31/2019 | 12/31/2018 | 12/31/2017 | 12/31/2016 |
| Revenues | 4,010.16 | 4,179.02 | 4,427.44 | 5,324.05 | 3,980.07 | 2,940.16 | 2,988.31 | 3,093.79 | 2,826.46 | 2,700.22 |
| Transportation operations | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Total revenues | 4,010.16 | 4,179.02 | 4,427.44 | 5,324.05 | 3,980.07 | 2,940.16 | 2,988.31 | 3,093.79 | 2,826.46 | 2,700.22 |
| OPERATING EXPENSES AND COSTS | 3,919.85 | 3,934.59 | 4,254.82 | 4,924.78 | 3,699.08 | 2,841.89 | 2,924.54 | 2,984.69 | 2,772.95 | 2,671.25 |
| Transportation operations | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Operating Income (Loss) | 90.31 | 244.43 | 172.62 | 399.27 | 280.99 | 98.28 | -- | 109.10 | 53.51 | 28.97 |
| Interest expense and other related financing costs | 12.36 | 8.98 | 9.09 | 7.70 | 8.90 | 11.70 | 11.47 | 9.47 | 6.34 | 5.15 |
| Net gains on sales of property and other | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Gain on sale of Wingfoot | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Gain on sale of Clipper LTL | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Gain on sale of G.I. Trucking Company | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Interest and dividend income | 4.76 | 11.62 | 14.73 | 3.96 | 1.28 | 3.62 | 6.45 | 3.91 | 1.29 | 1.52 |
| Short-term investment income | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Other, net | 0.39 | (28.36) | 8.66 | (2.37) | 3.80 | 2.30 | (7.29) | (19.16) | 3.12 | 2.94 |
| Fair value changes and payments on interest rate swap | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| IRS interest settlement | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Income (loss) before income taxes | 83.10 | 218.71 | 186.92 | 393.16 | 277.15 | 92.50 | 51.47 | 84.39 | 51.58 | 28.29 |
| Current- Foreign | -- | -- | 0.51 | 0.87 | 0.34 | 0.41 | 2.06 | 2.24 | -- | -- |
| Current: Federal | -- | -- | 38.86 | 80.38 | 56.45 | 10.00 | 2.20 | 9.75 | -- | -- |
| Current: State | -- | -- | 10.95 | 19.95 | 14.43 | 3.27 | 1.81 | 3.26 | -- | -- |
| Deferred: Foreign | -- | -- | 0.00 | (0.02) | 0.06 | (0.02) | (0.01) | (0.02) | -- | -- |
| FEDERAL AND STATE INCOME TAXES: Current | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| FEDERAL AND STATE INCOME TAXES: Deferred | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Deferred: Federal (credit) | -- | -- | (4.88) | (5.48) | (6.10) | 5.95 | 4.20 | 1.16 | -- | -- |
| Deferred: State (credit) | -- | -- | (0.68) | (0.75) | (1.55) | 1.79 | 1.22 | 0.74 | -- | -- |
| Income taxes (benefits) | 23.00 | 45.35 | 44.75 | 94.95 | 63.63 | 21.40 | 11.49 | 17.12 | (8.15) | 9.64 |
| Income from Continuing Operations | 60.10 | 173.36 | 142.16 | -- | -- | -- | -- | -- | -- | -- |
| Discontinued operations: Loss from discontinued operations | -- | 0.60 | 53.27 | -- | -- | -- | -- | -- | -- | -- |
| DISCONTINUED OPERATIONS: Gain from disposal | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| INCOME BEFORE CUMULATIVE EFFECT OF CHANGE IN ACCOUNTING PRINCIPLE | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Cumulative Effect of Change in Accounting Principle | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| NET INCOME before Preferred Stock Dividend | -- | 173.96 | -- | -- | -- | -- | -- | -- | -- | -- |
| Noncontrolling interest in net income of subsidiary | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Preferred stock dividends | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Effect of unvested restricted stock awards | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Net Income (Loss) Available to Common Shareholders | 60.10 | 173.96 | 195.43 | 298.21 | 213.52 | 71.10 | 39.99 | 67.26 | 59.73 | 18.65 |
| EPS (BASIC): Income from continuing operations | 2.63 | 7.36 | 5.92 | -- | -- | -- | -- | -- | -- | -- |
| EPS (BASIC): Income from discontinued operations | -- | 0.03 | 2.22 | -- | -- | -- | -- | -- | -- | -- |
| EPS (BASIC): Cumulative effect of change in accounting principle, net of tax | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Net Earnings Per Share (Basic) | 2.63 | 7.39 | 8.14 | 12.13 | 8.38 | 2.80 | 1.56 | 2.61 | 2.32 | 0.72 |
| EPS (DILUTED): Income from continuing operations | 2.62 | 7.28 | 5.77 | -- | -- | -- | -- | -- | -- | -- |
| EPS (DILUTED): Income from discontinued operations | -- | 0.03 | 2.16 | -- | -- | -- | -- | -- | -- | -- |
| EPS (DILUTED): Cumulative effect of change in accounting principle, net of tax | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Net Earnings Per Share (Diluted) | 2.62 | 7.30 | 7.93 | 11.69 | 7.98 | 2.69 | 1.51 | 2.51 | 2.25 | 0.71 |
| Weighted Average Shares Outstanding (Basic) | 22.84 | 23.55 | 24.02 | 24.59 | 25.47 | 25.41 | 25.54 | 25.68 | 25.68 | 25.75 |
| Weighted Average Shares Outstanding (Diluted) | 22.93 | 23.82 | 24.63 | 25.51 | 26.77 | 26.42 | 26.45 | 26.70 | 26.42 | 26.26 |