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INCOME AND SOCIAL CONTRIBUTION TAXES - Estimated recovery and reversal of income and social contributions tax assets and liabilities (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | --- | ---
Deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |  |
Non-current assets | R$ 3,054,393 | R$ 3,407,230 | R$ 4,307,462 | R$ 2,567,189
Non-current liabilities | (82,686) | (395,436) | R$ (914,475) | R$ (944,546)
Next 12 months |  |  |  |
Deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |  |
Non-current assets | 326,356 | 512,422 |  |
Non-current liabilities | (2,680) | (2,283) |  |
Year Two |  |  |  |
Deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |  |
Non-current assets | 198,590 | 391,384 |  |
Non-current liabilities | (6,116) | (89,052) |  |
Year Three |  |  |  |
Deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |  |
Non-current assets | 400,597 | 364,030 |  |
Non-current liabilities | (6,498) | (56,006) |  |
Year Four |  |  |  |
Deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |  |
Non-current assets | 369,857 | 535,937 |  |
Non-current liabilities | (4,745) | (154,664) |  |
After Year Four |  |  |  |
Deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |  |
Non-current assets | 1,758,993 |  |  |
Non-current liabilities | R$ (62,647) |  |  |
Year Five |  |  |  |
Deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |  |
Non-current assets |  | 499,984 |  |
Non-current liabilities |  | (14,496) |  |
After year 5 |  |  |  |
Deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |  |
Non-current assets |  | 1,103,473 |  |
Non-current liabilities |  | R$ (78,935) |  |

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- Definition The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph g -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_g_i&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 54 -Subparagraph o -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_o&doctype=Standard -URIDate 2017-03-09 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 56 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_56&doctype=Standard -URIDate 2017-03-09 + Details
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