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INCOME AND SOCIAL CONTRIBUTION TAXES - Changes in net deferred asset (liability) (Details) - BRL (R$) R$ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | R$ 3,011,794 | R$ 3,392,987 | R$ 1,622,643
Recognized in income | 18,367 | (193,803) | 1,656,872
Effect of selling of subsidiary and others | 2,056 | (211,897) |
Comprehensive Income | (60,510) | 24,507 | 113,472
Balance as of end of period | 2,971,707 | 3,011,794 | 3,392,987
Tax loss carryforward |  |  |
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | 874,357 | 887,980 | 1,003,441
Recognized in income | 157,402 | 327,743 | (259,976)
Effect of selling of subsidiary and others | (22,362) | (263,297) |
Comprehensive Income | (35,759) | (78,069) | 144,515
Balance as of end of period | 973,638 | 874,357 | 887,980
Social contribution tax losses |  |  |
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | 311,892 | 191,638 | 148,827
Recognized in income | 58,963 | 120,254 | 42,811
Effect of selling of subsidiary and others | (15,073) |  |
Balance as of end of period | 355,782 | 311,892 | 191,638
Provision for tax, civil and labor liabilities |  |  |
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | 755,198 | 639,566 | 527,731
Recognized in income | (479,836) | 118,526 | 110,318
Effect of selling of subsidiary and others | 101 | (2,671) |
Comprehensive Income |  | (223) | 1,517
Balance as of end of period | 275,463 | 755,198 | 639,566
Benefits granted to employees |  |  |
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | 432,537 | 549,865 | 431,328
Recognized in income | (48,466) | (67,133) | (25,694)
Effect of selling of subsidiary and others | (9,363) | 34,982 |
Comprehensive Income | (91,905) | (85,177) | 144,231
Balance as of end of period | 282,803 | 432,537 | 549,865
Other temporary differences |  |  |
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | 350,762 | 381,991 | 210,609
Recognized in income | (81,627) | (21,985) | 247,458
Effect of selling of subsidiary and others | 92,174 | 20,776 |
Comprehensive Income | 48,991 | (30,020) | (76,076)
Balance as of end of period | 410,300 | 350,762 | 381,991
Deferred exchange variance |  |  |
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | 1,251,542 | 2,158,149 | 874,742
Recognized in income | (199,200) | (907,690) | 1,292,709
Effect of selling of subsidiary and others | 8,185 |  |
Comprehensive Income |  | 1,083 | (9,302)
Balance as of end of period | 1,060,527 | 1,251,542 | 2,158,149
Provision for losses |  |  |
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | 112,936 | 151,678 | 54,938
Recognized in income | (2,208) | (34,059) | 95,596
Effect of selling of subsidiary and others |  | (4,671) |
Comprehensive Income |  | (12) | 1,144
Balance as of end of period | 110,728 | 112,936 | 151,678
Difference between book value and tax base of assets acquired in business combinations |  |  |
Breakdown and changes in deferred income and social contribution tax assets and liabilities at statutory tax rates |  |  |
Balance as of beginning of period | (1,077,430) | (1,567,880) | (1,628,973)
Recognized in income | 613,339 | 270,541 | 153,650
Effect of selling of subsidiary and others | (51,606) | 2,984 |
Comprehensive Income | 18,163 | 216,925 | (92,557)
Balance as of end of period | R$ (497,534) | R$ (1,077,430) | R$ (1,567,880)

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- Definition The decrease in deferred tax liability (asset) resulting from the loss of control of a subsidiary and other deferred tax liabilities (assets). + References No definition available. + Details
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- Definition The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph g -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_g_ii&doctype=Standard -URIDate 2017-03-09 + Details
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