5. Risk Management (Details 4) - BRL (R$) R$ in Thousands	Dec. 31, 2018	Dec. 31, 2017
SummaryOfRiskManagementLineItems [Line Items]
Borrowings and financing	R$ 16,104,306
Accounts payables to suppliers and contractors	465,993
Services payable	454,022	R$ 408,275
Public-Private Partnership - PPP	6,803,620
Program contract commitments	412,194
2019
SummaryOfRiskManagementLineItems [Line Items]
Borrowings and financing	2,581,359
Accounts payables to suppliers and contractors	465,993
Services payable	454,022
Public-Private Partnership - PPP	405,263
Program contract commitments	244,446
2020
SummaryOfRiskManagementLineItems [Line Items]
Borrowings and financing	3,073,006
Accounts payables to suppliers and contractors	0
Services payable	0
Public-Private Partnership - PPP	377,196
Program contract commitments	45,608
2021
SummaryOfRiskManagementLineItems [Line Items]
Borrowings and financing	1,427,558
Accounts payables to suppliers and contractors	0
Services payable	0
Public-Private Partnership - PPP	377,196
Program contract commitments	45,741
2022
SummaryOfRiskManagementLineItems [Line Items]
Borrowings and financing	1,468,221
Accounts payables to suppliers and contractors	0
Services payable	0
Public-Private Partnership - PPP	377,196
Program contract commitments	30,991
2023
SummaryOfRiskManagementLineItems [Line Items]
Borrowings and financing	1,189,927
Accounts payables to suppliers and contractors	0
Services payable	0
Public-Private Partnership - PPP	377,196
Program contract commitments	30,991
2024 onwards
SummaryOfRiskManagementLineItems [Line Items]
Borrowings and financing	6,364,235
Accounts payables to suppliers and contractors	0
Services payable	0
Public-Private Partnership - PPP	4,889,573
Program contract commitments	R$ 14,417

The amount of outstanding funds that the entity is obligated to repay.

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Public-Private Partnerships, or &#8220;PPPs&#8221;, are long-term contracts between private parties and government entities, for providing a public asset or service, in which the private parties bears significant risk and management responsibility, and remuneration is linked to performance. PPPs are regulated by the State of S&#227;o Paulo through Law No. 11,688/2004, which was enacted on May 19, 2004. PPPs may be used for: (i) implantation, expansion, improvement, reform, maintenance or management of public infrastructure; (ii) provision of public services; and (iii) exploitation of public assets and non material rights belonging to the State.

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The amount of future capital expenditures that the entity is committed to make.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount of current provisions other than provisions for employee benefits. [Refer: Provisions]

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The amount of current trade payables and current other payables. [Refer: Current trade payables; Other current payables]

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