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Financial Instruments and Risk Management - Additional Information (Details) $ in Millions |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 19, 2023 | Dec. 05, 2023 | Jun. 14, 2023 USD ($) | Apr. 13, 2023 BRL (R$) | Apr. 13, 2023 USD ($) | Jun. 30, 2023 USD ($) | Jun. 30, 2023 BRL (R$) | Dec. 31, 2023 BRL (R$) | Dec. 31, 2022 BRL (R$) | Dec. 31, 2021 BRL (R$) | May 12, 2023 BRL (R$) | Dec. 31, 2020 BRL (R$)
Financial instruments and risk management [line items] |  |  |  |  |  |  |  |  |  |  |  |
Interest on swap settled in cash flow |  |  |  |  |  |  |  | R$ 99,000,000 | R$ 95,000,000 |  |  |
Percentage of fair value of loans and debentures on CDI rates |  |  |  |  |  |  |  | 123.85% |  |  |  |
Cash flow hedge partially disassembled | $ |  |  |  |  |  | $ 369 |  |  |  |  |  |
Gain on cash flow hedge dismantled |  |  |  |  |  |  | R$ 283,000,000 |  |  |  |  |
Hedge dismantled on cash inflow |  |  |  |  |  |  | 241,000,000 |  |  |  |  |
Short-term hedge |  |  | $ 376 | R$ 5,111,000 | $ 392 |  |  |  |  |  |  |
Maturity of short-term hedge contract | Dec. 19, 2023 | Dec. 05, 2023 |  |  |  |  |  |  |  |  |  |
Settlement of forward exchange derivative contract |  |  |  |  |  |  |  | R$ 117,000,000 |  |  |  |
Derivative adjustment |  |  |  |  |  |  |  | 177,000,000 | 438,000,000 |  |  |
Total current |  |  |  |  |  |  |  | 368,000,000 | 612,000,000 |  |  |
Notional amount |  |  |  |  |  |  |  | 445,000,000 | 996,000,000 |  |  |
Fair value of financial instrument |  |  |  |  |  |  |  | 497,000,000 |  |  |  |
Appreciation to excahange of foreign currencies, amount |  |  |  |  |  |  |  | R$ 4,980,000 |  |  |  |
Average foreign currencies exchange rate |  |  |  |  |  |  |  | 2.86 |  |  |  |
Estimated contract credits in arrears receivable |  |  |  |  |  |  |  | R$ 910,000,000 | 820,000,000 |  |  |
Minimum equity required for concession of credit |  |  |  |  |  |  |  | R$ 800,000,000 |  |  |  |
Basel ratio percentage required above minimum set by regulating bank |  |  |  |  |  |  |  | 1.00% |  |  |  |
Percentage of estimated IPCA inflation index |  |  |  |  |  |  |  | 4.23% |  |  |  |
Percentage of estimated IGPM inflation index |  |  |  |  |  |  |  | 3.81% |  |  |  |
Percentage of maximum portfolio limit per bank entity |  |  |  |  |  |  |  | 30.00% |  |  |  |
Percentage of minimum fedreal risk concentrate |  |  |  |  |  |  |  | 50.00% |  |  |  |
Percentage of regulatory agent limits for consumer exposure |  |  |  |  |  |  |  | 100.00% |  |  |  |
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financial instruments and risk management [line items] |  |  |  |  |  |  |  |  |  |  |  |
Percentage of fair value of loans and debentures on CDI rates |  |  |  |  |  |  |  | 1.18% |  |  |  |
Percentage of fair value of loans and debentures on IPCA |  |  |  |  |  |  |  | 4.10% |  |  |  |
Percentage of regulatory agent margin distributor supply |  |  |  |  |  |  |  | 95.00% |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financial instruments and risk management [line items] |  |  |  |  |  |  |  |  |  |  |  |
Percentage of fair value of loans and debentures on CDI rates |  |  |  |  |  |  |  | 6.96% |  |  |  |
Percentage of fair value of loans and debentures on IPCA |  |  |  |  |  |  |  | 7.62% |  |  |  |
Percentage of regulatory agent margin distributor supply |  |  |  |  |  |  |  | 105.00% |  |  |  |
Probable Ccenario [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financial instruments and risk management [line items] |  |  |  |  |  |  |  |  |  |  |  |
Financial instrument positive effect on swap and call spread, amount |  |  |  |  |  |  |  | R$ 129,000,000 |  |  |  |
Percentage of estimated IPCA inflation index |  |  |  |  |  |  |  | 4.23% |  |  |  |
Percentage of estimated IGPM inflation index |  |  |  |  |  |  |  | 3.81% |  |  |  |
Swap Contracts [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financial instruments and risk management [line items] |  |  |  |  |  |  |  |  |  |  |  |
Notional amount |  |  |  |  |  |  |  | R$ 445,000,000 | 997,000,000 |  |  |
Put option - SAAG [member] |  |  |  |  |  |  |  |  |  |  |  |
Financial instruments and risk management [line items] |  |  |  |  |  |  |  |  |  |  |  |
Derivative financial liabilities |  |  |  |  |  |  |  | 0 | 672,000,000 | R$ 636,000,000 | R$ 780,000,000 | R$ 536,000,000
Adjustment to fair value |  |  |  |  |  |  | R$ 25,000,000 | R$ 58,000,000 | R$ 36,000,000 | R$ 100,000,000 |  |
Selic interest rate [Member] | Probable Ccenario [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financial instruments and risk management [line items] |  |  |  |  |  |  |  |  |  |  |  |
Significant interest rate risk |  |  |  |  |  |  |  | 9.25% |  |  |  |
TJLP interest rate [member] | Probable Ccenario [Member] |  |  |  |  |  |  |  |  |  |  |  |
Financial instruments and risk management [line items] |  |  |  |  |  |  |  |  |  |  |  |
Significant interest rate risk |  |  |  |  |  |  |  | 6.27% |  |  |  |

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