Stockholders' equity - Schedule of Capital Reserves and Revenue Reserves (Details) - BRL (R$) R$ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Disclosure of reserves within equity [line items] | ||
| Capital reserves | R$ 2,876 | R$ 2,732 |
| Total reserves at parent company | 70,587 | 124,160 |
| Premium on subscription of shares | ||
| Disclosure of reserves within equity [line items] | ||
| Capital reserves | 284 | 284 |
| Share-based payment | ||
| Disclosure of reserves within equity [line items] | ||
| Capital reserves | 2,588 | 2,444 |
| Profit reserves | 67,711 | 121,428 |
| Reserves from tax incentives, restatement of equity securities and other | ||
| Disclosure of reserves within equity [line items] | ||
| Capital reserves | 4 | 4 |
| Legal | ||
| Disclosure of reserves within equity [line items] | ||
| Profit reserves | 20,429 | 18,146 |
| Statutory | ||
| Disclosure of reserves within equity [line items] | ||
| Profit reserves | 47,282 | 87,793 |
| Special revenue | ||
| Disclosure of reserves within equity [line items] | ||
| Profit reserves | R$ 0 | R$ 15,489 |