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15. CONCESSION CONTRACT ASSETS (Details 2) - BRL (R$) R$ in Millions | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration | R$ 737 |  |
Non current consideration | 3,008 |  |
Total consideration | 3,745 |  |
Restated [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration |  | R$ 576 | R$ 482
Non current consideration |  | 2,500 | 2,427
Total consideration |  | 3,076 | 2,909
Concession contract - 004/05 [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration | 19 |  |
Non current consideration | 91 |  |
Concession contract - 004/05 [member] | Restated [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration |  |  |
Non current consideration |  |  |
Concession contract - 079/00 [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration | 29 |  |
Non current consideration | 133 |  |
Concession contract - 079/00 [member] | Restated [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration |  | 21 | 19
Non current consideration |  | 95 | 93
Basic Network of the Existing System (BNES) [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration | 533 |  |
Non current consideration | 1,363 |  |
Basic Network of the Existing System (BNES) [member] | Restated [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration |  | 434 | 347
Non current consideration |  | 1,494 | 1,714
Basic Network of New Facilities (BNNF) [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration | 156 |  |
Non current consideration | R$ 1,421 |  |
Basic Network of New Facilities (BNNF) [member] | Restated [member] |  |  |
ConcessionContractAssetsLineItems [Line Items] |  |  |
Current consideration |  | 121 | 116
Non current consideration |  | R$ 911 | R$ 620

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