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FINANCIAL INSTRUMENTS - Fair value of financial instruments (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
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FINANCIAL INSTRUMENTS |  |
Financial assets | R$ 1,750,841 | R$ 1,886,067
Financial liabilities | 17,339,894 | 18,925,008
Loans and Financing |  |
FINANCIAL INSTRUMENTS |  |
Financial liabilities | 13,367,841 | 16,461,656
Financial liabilities, at fair value | 13,533,306 | 17,102,512
Debentures |  |
FINANCIAL INSTRUMENTS |  |
Financial liabilities | 1,538,873 | 47,928
Financial liabilities, at fair value | 1,538,873 | 47,928
Unrealized losses on financial instruments |  |
FINANCIAL INSTRUMENTS |  |
Financial liabilities | 5,245 | 1,267
Financial liabilities, at fair value | 5,245 | 1,267
Obligation with FIDC |  |
FINANCIAL INSTRUMENTS |  |
Financial liabilities | 938,526 | 1,135,077
Financial liabilities, at fair value | 938,526 | 1,135,077
Other current liabilities |  |
FINANCIAL INSTRUMENTS |  |
Financial liabilities | 988,967 | 625,410
Financial liabilities, at fair value | 988,967 | 625,410
Other non-current liabilities |  |
FINANCIAL INSTRUMENTS |  |
Financial liabilities | 499,092 | 653,670
Financial liabilities, at fair value | 499,092 | 653,670
Short-term investments |  |
FINANCIAL INSTRUMENTS |  |
Financial assets | 459,470 | 821,518
Financial assets, at fair value | 459,470 | 821,518
Related parties |  |
FINANCIAL INSTRUMENTS |  |
Financial assets | 27,939 | 51,839
Financial assets, at fair value | 27,939 | 51,839
Financial liabilities | 1,350 |
Unrealized gains on financial instruments |  |
FINANCIAL INSTRUMENTS |  |
Financial assets | 33,417 |
Financial assets, at fair value | 33,417 |
Other current assets |  |
FINANCIAL INSTRUMENTS |  |
Financial assets | 780,423 | 469,737
Financial assets, at fair value | 780,423 | 469,737
Other non-current assets |  |
FINANCIAL INSTRUMENTS |  |
Financial assets | 449,592 | 542,973
Financial assets, at fair value | R$ 449,592 | R$ 542,973

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- Definition The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_25&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 35H -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_35H&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 35I -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_35I&doctype=Standard -URIDate 2018-03-16 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 35M -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_35M&doctype=Standard -URIDate 2018-03-16 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 35N -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_35N&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2018-01-01 -Paragraph 25 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2018-03-01&anchor=para_25&doctype=Standard -URIDate 2018-03-16 + Details
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