| Schedule of Debt [Table Text Block] |
| (in thousands) | | September 30, 2026 | | | December 31, 2025 | |
| | | Current | | | Long-Term | | | Current | | | Long-Term | |
| Borrowings under Credit Facility | | $ | - | | | $ | 35,061 | | | $ | - | | | $ | 30,000 | |
| Equipment installment notes; weighted average interest rate of 5.1% at September 30, 2026, and 5.1% at December 31, 2025, due in monthly installments with final maturities at various dates ranging from February 2027 to September 2032, secured by related equipment (1) | | | 66,513 | | | | 167,729 | | | | 62,602 | | | | 189,115 | |
| Real estate notes; interest rate of 5.5% at September 30, 2026 and 5.6% at December 31, 2025 due in monthly installments with a fixed maturity at August 2035, secured by related real estate | | | 1,611 | | | | 13,683 | | | | 1,403 | | | | 14,931 | |
| Total debt | | | 68,124 | | | | 216,473 | | | | 64,005 | | | | 234,046 | |
| Principal portion of finance lease obligations, secured by related revenue equipment | | | 1,254 | | | | 1,811 | | | | 840 | | | | 2,353 | |
| Principal portion of operating lease obligations, secured by related real estate and revenue equipment | | | 12,498 | | | | 16,566 | | | | 12,182 | | | | 25,272 | |
| Total debt and lease obligations | | $ | 81,876 | | | $ | 234,850 | | | $ | 77,027 | | | $ | 261,671 | |
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