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v3.23.1

IMPAIRMENT OF ASSETS (Details) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 BRL (R$) segment | Dec. 31, 2021 BRL (R$) | Dec. 31, 2020 BRL (R$)
Impairment of assets |  |  |
Impairment of property, plant and equipment | R$ 0 | R$ 0 | R$ 411,925
Number of operating segments | segment | 4 |  |
Impairment of goodwill | R$ 0 | R$ 0 | 0
Period for projecting the cash flows for the goodwill impairment test | five years |  |
Discount rate | Sensitivity analysis, increase of 5% |  |  |
Impairment of assets |  |  |
Sensitivity analysis, percent of increase | 0.50% | 0.50% |
Perpetuity growth rate | Sensitivity analysis, decrease of 5% |  |  |
Impairment of assets |  |  |
Sensitivity analysis, percent of decrease | 0.50% | 0.50% |
North America |  |  |
Impairment of assets |  |  |
Impairment of property, plant and equipment |  |  | 342,355
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 10,426,000 | R$ 5,769,000 |
North America | Discount rate | Sensitivity analysis, increase of 5% |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 8,749,000 | R$ 4,337,000 |
North America | Post-tax discount rates |  |  |
Impairment of assets |  |  |
Discount rate | 9.75% | 9.50% |
North America | Pre-tax discount rates |  |  |
Impairment of assets |  |  |
Discount rate | 12.28% | 12.05% |
North America | Perpetuity growth rate |  |  |
Impairment of assets |  |  |
Growth rate | 3.00% | 3.00% |
North America | Perpetuity growth rate | Sensitivity analysis, decrease of 5% |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 9,161,000 | R$ 4,679,000 |
Special Steel |  |  |
Impairment of assets |  |  |
Impairment of property, plant and equipment |  |  | R$ 69,570
Amount by which unit's recoverable amount is (below) exceeds its carrying value | 5,299,000 | 4,238,000 |
Special Steel | Discount rate | Sensitivity analysis, increase of 5% |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 4,329,000 | R$ 3,301,000 |
Special Steel | Post-tax discount rates |  |  |
Impairment of assets |  |  |
Discount rate | 10.75% | 10.50% |
Special Steel | Pre-tax discount rates |  |  |
Impairment of assets |  |  |
Discount rate | 13.81% | 13.29% |
Special Steel | Perpetuity growth rate |  |  |
Impairment of assets |  |  |
Growth rate | 3.00% | 3.00% |
Special Steel | Perpetuity growth rate | Sensitivity analysis, decrease of 5% |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 4,586,000 | R$ 3,545,000 |
South America |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | 1,074,000 | 2,248,000 |
South America | Discount rate | Sensitivity analysis, increase of 5% |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 953,000 | R$ 2,057,000 |
South America | Post-tax discount rates |  |  |
Impairment of assets |  |  |
Discount rate | 18.00% | 15.00% |
South America | Pre-tax discount rates |  |  |
Impairment of assets |  |  |
Discount rate | 26.47% | 21.21% |
South America | Perpetuity growth rate |  |  |
Impairment of assets |  |  |
Growth rate | 3.00% | 3.00% |
South America | Perpetuity growth rate | Sensitivity analysis, decrease of 5% |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 1,011,000 | R$ 2,135,000 |
Brazil |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | 3,632,000 | 8,994,000 |
Brazil | Discount rate | Sensitivity analysis, increase of 5% |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 2,306,000 | R$ 7,582,000 |
Brazil | Post-tax discount rates |  |  |
Impairment of assets |  |  |
Discount rate | 11.75% | 11.25% |
Brazil | Pre-tax discount rates |  |  |
Impairment of assets |  |  |
Discount rate | 15.56% | 15.13% |
Brazil | Perpetuity growth rate |  |  |
Impairment of assets |  |  |
Growth rate | 3.00% | 3.00% |
Brazil | Perpetuity growth rate | Sensitivity analysis, decrease of 5% |  |  |
Impairment of assets |  |  |
Amount by which unit's recoverable amount is (below) exceeds its carrying value | R$ 2,673,000 | R$ 7,962,000 |

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