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DEBENTURES - Amortization schedules (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
DEBENTURES |  |
Debentures | R$ 47,928 | R$ 165,423
Debentures |  |
DEBENTURES |  |
Nominal annual interest rate (as a percent) | 9.93% | 14.00%
Year Three |  |
DEBENTURES |  |
Debentures | R$ 5,761 |
Year Four |  |
DEBENTURES |  |
Debentures | 21,377 | R$ 17,267
Year Five |  |
DEBENTURES |  |
Debentures | 14,557 | 44,292
Year Six |  |
DEBENTURES |  |
Debentures |  | 57,191
After year 5 |  |
DEBENTURES |  |
Debentures | R$ 6,233 |
After Year Six |  |
DEBENTURES |  |
Debentures |  | R$ 46,673

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