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BUSINESS SEGMENTS (Summary of Certain Financial Information from Continuing Operations by Reportable Segment and Major Product) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
May 31, 2024 | May 31, 2023 | May 31, 2024 | May 31, 2023 | Aug. 31, 2023
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | $ 2,078,485 | $ 2,344,989 | $ 5,929,823 | $ 6,590,305 |
Adjusted EBITDA reportable segments | 280,332 | 411,793 | 848,568 | 1,166,514 |
Total assets | 6,710,231 | 6,639,094 | 6,710,231 | 6,639,094 | $ 6,639,094
Unaffiliated Customers |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales |  |  | 5,929,823 | 6,590,305 |
Raw materials |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 401,675 | 393,073 | 1,048,187 | 1,013,961 |
Steel products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 816,323 | 1,018,735 | 2,420,103 | 2,935,678 |
Downstream products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 665,832 | 708,060 | 1,896,285 | 2,002,567 |
Construction products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 73,117 | 86,505 | 216,343 | 245,503 |
Ground stabilization solutions |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 69,451 | 69,628 | 171,909 | 177,621 |
Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 52,087 | 68,988 | 176,996 | 214,975 |
North America Steel Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 1,690,853 | 1,842,422 | 4,808,246 | 5,057,924 |
Europe Steel Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 209,543 | 331,336 | 628,852 | 1,056,594 |
Emerging Businesses Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 196,634 | 192,677 | 542,107 | 532,733 |
Corporate and Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | (18,545) | (21,446) | (49,382) | (56,946) |
Segments |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 2,068,757 | 2,338,213 | 5,898,517 | 6,554,343 |
Adjusted EBITDA reportable segments | 280,332 | 411,793 | 848,568 | 1,166,514 |
Total assets | 5,821,059 | 5,968,319 | 5,821,059 | 5,968,319 |
Segments | North America Steel Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 1,671,358 | 1,818,391 | 4,750,210 | 4,986,326 |
Adjusted EBITDA reportable segments | 246,304 | 367,561 | 735,418 | 991,588 |
Total assets | 4,261,895 | 4,166,521 | 4,261,895 | 4,166,521 |
Segments | North America Steel Group | Unaffiliated Customers |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales |  |  | 4,750,210 | 4,986,326 |
Segments | North America Steel Group | Raw materials |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 396,954 | 387,106 | 1,035,615 | 998,233 |
Segments | North America Steel Group | Steel products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 648,618 | 749,623 | 1,918,686 | 2,082,023 |
Segments | North America Steel Group | Downstream products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 594,329 | 631,964 | 1,684,584 | 1,766,423 |
Segments | North America Steel Group | Construction products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | North America Steel Group | Ground stabilization solutions |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | North America Steel Group | Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 31,457 | 49,698 | 111,325 | 139,647 |
Segments | Europe Steel Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 208,806 | 330,767 | 626,481 | 1,054,830 |
Adjusted EBITDA reportable segments | (4,192) | 5,837 | 26,139 | 78,554 |
Total assets | 713,394 | 927,468 | 713,394 | 927,468 |
Segments | Europe Steel Group | Unaffiliated Customers |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales |  |  | 626,481 | 1,054,830 |
Segments | Europe Steel Group | Raw materials |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 4,721 | 5,967 | 12,572 | 15,728 |
Segments | Europe Steel Group | Steel products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 167,705 | 269,112 | 501,417 | 853,655 |
Segments | Europe Steel Group | Downstream products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 29,599 | 46,448 | 91,744 | 156,158 |
Segments | Europe Steel Group | Construction products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Europe Steel Group | Ground stabilization solutions |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Europe Steel Group | Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 6,781 | 9,240 | 20,748 | 29,289 |
Segments | Emerging Businesses Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 188,593 | 189,055 | 521,826 | 513,187 |
Adjusted EBITDA reportable segments | 38,220 | 38,395 | 87,011 | 96,372 |
Total assets | 845,770 | 874,330 | 845,770 | 874,330 |
Segments | Emerging Businesses Group | Unaffiliated Customers |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales |  |  | 521,826 | 513,187 |
Segments | Emerging Businesses Group | Raw materials |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Emerging Businesses Group | Steel products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Emerging Businesses Group | Downstream products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 41,904 | 29,648 | 119,957 | 79,986 |
Segments | Emerging Businesses Group | Construction products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 73,117 | 86,505 | 216,343 | 245,503 |
Segments | Emerging Businesses Group | Ground stabilization solutions |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 69,451 | 69,628 | 171,909 | 177,621 |
Segments | Emerging Businesses Group | Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 4,121 | 3,274 | 13,617 | 10,077 |
Segments | Corporate and Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 9,728 | 6,776 | 31,306 | 35,962 |
Total assets | 889,172 | 670,775 | 889,172 | 670,775 |
Segments | Corporate and Other | Unaffiliated Customers |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales |  |  | 31,306 | 35,962 |
Segments | Corporate and Other | Raw materials |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Corporate and Other | Steel products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Corporate and Other | Downstream products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Corporate and Other | Construction products |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Corporate and Other | Ground stabilization solutions |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 0 | 0 | 0 | 0 |
Segments | Corporate and Other | Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 9,728 | 6,776 | 31,306 | 35,962 |
Intersegment | North America Steel Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 19,495 | 24,031 | 58,036 | 71,598 |
Intersegment | Europe Steel Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 737 | 569 | 2,371 | 1,764 |
Intersegment | Emerging Businesses Group |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | 8,041 | 3,622 | 20,281 | 19,546 |
Intersegment | Corporate and Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net sales | $ (28,273) | $ (28,222) | $ (80,688) | $ (92,908) |

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