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RELATED-PARTY TRANSACTIONS - Key Management compensation (Details) | 12 Months Ended
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Dec. 31, 2018 BRL (R$) Options EquityInstruments | Dec. 31, 2017 BRL (R$) Options EquityInstruments | Dec. 31, 2016 BRL (R$) Options EquityInstruments
Key Management personnel |  |  |
RELATED PARTY TRANSACTIONS |  |  |
Key management salaries, variable compensation and benefits | R$ 50,310,000 | R$ 38,510,000 |
Contributions to defined contribution pension plans | 1,595,000 | 1,158,000 |
Long term incentive plan attributable to key management | R$ 23,189,000 | R$ 10,451,000 | R$ 14,095,000
Stock options |  |  |
Number of shares |  |  |
Balance, beginning of year | Options | 292,391 | 569,115 | 1,074,246
Options Cancelled | Options | (243,412) | (276,724) | (505,131)
Balance, end of year | Options | 15,480 | 292,391 | 569,115
Weighted exercise price |  |  |
Beginning of year | R$ 17.91 | R$ 16.64 | R$ 18.36
Options Cancelled | 18.62 | 15.11 | 20.49
End of year | R$ 16.72 | R$ 17.91 | R$ 16.64
Stock options | Key Management personnel |  |  |
Number of shares |  |  |
Balance, beginning of year | Options | 198,000 |  |
Options Cancelled | Options | (198,000) |  |
Balance, end of year | Options |  | 198,000 |
Weighted exercise price |  |  |
Beginning of year | R$ 18.19 |  |
Options Cancelled | R$ 18.62 |  |
End of year |  | R$ 18.19 |
Restricted shares | Key Management personnel |  |  |
Restricted shares granted to Management |  |  |
Balance, beginning of year | EquityInstruments | 5,945,310 | 4,831,999 |
Granted | EquityInstruments | 1,255,286 | 1,353,930 |
Exercised | EquityInstruments | (511,333) | (240,619) |
Shares adjustment | EquityInstruments | (313,716) |  |
Balance, end of year | EquityInstruments | 6,375,547 | 5,945,310 | 4,831,999

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