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LONG-TERM INCENTIVE PLANS - Other plans (Details) $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2017 USD ($) EquityInstruments Options | Dec. 31, 2016 USD ($) EquityInstruments Options | Dec. 31, 2016 BRL (R$) EquityInstruments | Dec. 31, 2015 USD ($) EquityInstruments Options | Dec. 31, 2015 BRL (R$) EquityInstruments Options | Dec. 31, 2017 BRL (R$) EquityInstruments Options | Dec. 31, 2016 BRL (R$) Options | Dec. 31, 2014 Options
Stock options |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Outstanding shares (in shares) | Options | 292,391 | 569,115 |  | 1,074,246 | 1,074,246 | 292,391 | 569,115 | 2,448,973
North American subsidiary |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Outstanding liability for share-based payment transactions | $ 9 | $ 10 |  |  |  | R$ 29,800 | R$ 32,600 |
EIP | North American subsidiary |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Amount of shares granted under plan |  | $ 9,900 | R$ 34,500,000 | $ 13,900 | R$ 46,400,000 |  |  |
Vesting period (in years) |  | 5 years | 5 years | 5 years | 5 years |  |  |
EIP | North American subsidiary | Stock options | Maximum |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Term of grant (in years) | 10 years |  |  |  |  |  |  |
EIP | North American subsidiary | SARs | Maximum |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Term of grant (in years) | 10 years |  |  |  |  |  |  |
EIP | North American subsidiary | RSUs |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Shares issued under plan (in shares) |  | 2,846,835 | 2,846,835 | 3,833,542 | 3,833,542 |  |  |
EIP | North American subsidiary | PSUs |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Shares issued under plan (in shares) |  | 3,820,894 | 3,820,894 | 1,792,456 | 1,792,456 |  |  |
LTIP |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Vesting period (in years) | 4 years |  |  |  |  |  |  |
LTIP | Stock options |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Outstanding shares (in shares) | Options | 40,873 |  |  |  |  | 40,873 |  |
LTIP | SARs |  |  |  |  |  |  |  |
LONG-TERM INCENTIVE PLANS |  |  |  |  |  |  |  |
Outstanding shares (in shares) | 535,543 |  |  |  |  | 535,543 |  |

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