| Segment Reporting [Table Text Block] |
| | | Three Months Ended June 30, 2026 | |
| | | Flat-roll | | | Tubular | | | Other | | | Total | |
| Net Sales | | $ | 221,753 | | | $ | 18,218 | | | $ | — | | | $ | 239,971 | |
| Cost and expenses: | | | | | | | | | | | | | | | | |
| Cost of materials sold | | | 171,501 | | | | 12,718 | | | | — | | | | 184,219 | |
| Processing and warehousing expense | | | 10,717 | | | | 2,710 | | | | — | | | | 13,427 | |
| Delivery expense | | | 9,050 | | | | 335 | | | | — | | | | 9,385 | |
| Commercial expense | | | 4,833 | | | | 251 | | | | — | | | | 5,084 | |
| Depreciation and amortization | | | 906 | | | | 81 | | | | 82 | | | | 1,069 | |
| General corporate expenses | | | — | | | | — | | | | 5,753 | | | | 5,753 | |
| | | | 197,007 | | | | 16,095 | | | | 5,835 | | | | 218,937 | |
| EARNINGS (LOSS) FROM OPERATIONS: | | | 24,746 | | | | 2,123 | | | | (5,835 | ) | | | 21,034 | |
| Loss on economic hedges of risk | | | | | | | | | | | | | | | (2,756 | ) |
| Interest expense | | | | | | | | | | | | | | | (1,224 | ) |
| Other expense | | | | | | | | | | | | | | | (77 | ) |
| EARNINGS BEFORE INCOME TAXES | | | | | | | | | | | | | | $ | 16,977 | |
| | | | | | | | | | | | | | | | | |
| | | Three Months Ended June 30, 2025 | |
| | | Flat-roll | | | Tubular | | | Other | | | Total | |
| Net Sales | | $ | 124,067 | | | $ | 10,710 | | | $ | — | | | $ | 134,777 | |
| Cost and expenses: | | | | | | | | | | | | | | | | |
| Cost of materials sold | | | 99,154 | | | | 6,550 | | | | — | | | | 105,704 | |
| Processing and warehousing expense | | | 6,899 | | | | 2,429 | | | | — | | | | 9,328 | |
| Delivery expense | | | 6,260 | | | | 140 | | | | — | | | | 6,400 | |
| Commercial expense | | | 2,199 | | | | 212 | | | | — | | | | 2,411 | |
| Depreciation and amortization | | | 769 | | | | 50 | | | | 28 | | | | 847 | |
| General corporate expenses | | | — | | | | — | | | | 3,044 | | | | 3,044 | |
| | | | 115,281 | | | | 9,381 | | | | 3,072 | | | | 127,734 | |
| EARNINGS (LOSS) FROM OPERATIONS: | | | 8,786 | | | | 1,329 | | | | (3,072 | ) | | | 7,043 | |
| Gain on economic hedges of risk | | | | | | | | | | | | | | | 276 | |
| Interest expense | | | | | | | | | | | | | | | (678 | ) |
| Other income | | | | | | | | | | | | | | | 4 | |
| EARNINGS BEFORE INCOME TAXES | | | | | | | | | | | | | | $ | 6,645 | |
| | | June 30, 2026 | | | March 31, 2026 | |
| IDENTIFIABLE ASSETS: | | | | | | | | |
| Flat-Roll | | $ | 329,262 | | | $ | 301,528 | |
| Tubular | | | 34,948 | | | | 28,822 | |
| | | | 364,210 | | | | 330,350 | |
| General corporate assets | | | 9,228 | | | | 6,460 | |
| | | $ | 373,438 | | | $ | 336,810 | |
|