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FINANCIAL INSTRUMENTS - Swap Contracts (Details) R$ in Thousands, $ in Millions | Dec. 31, 2018 USD ($) | Dec. 31, 2018 BRL (R$) | Dec. 31, 2017 USD ($) | Dec. 31, 2017 BRL (R$)
--- | --- | --- | --- | ---
Swap Contracts |  |  |  |
Notional value |  | R$ 13,178,457 |  | R$ 16,207,120
Assets, Fair value |  |  |  |
Swap Contracts |  |  |  |
Amount receivable |  | 33,417 |  |
Amount payable |  | (5,245) |  | (1,267)
Forward contract | Forward contracts maturing at 2019 long position |  |  |  |
Swap Contracts |  |  |  |
Notional value | $ | $ 19.2 |  |  |
Amount payable |  | (4,069) |  |
Forward contract | Forward contracts maturing at 2019 short position |  |  |  |
Swap Contracts |  |  |  |
Notional value | $ | $ 18.3 |  |  |
Amount receivable |  | 462 |  |
Amount payable |  | R$ (1,176) |  |
Currency swap | Currency swap maturing in 2018 |  |  |  |
Swap Contracts |  |  |  |
Notional value | $ |  |  | $ 40.0 |
Amount payable |  |  |  | R$ (1,267)
Currency swap | Currency swap maturing in 2018 | INR |  |  |  |
Swap Contracts |  |  |  |
Fixed interest rate (as a percent) | 10.17% | 10.17% | 10.17% | 10.17%
Currency swap | Currency swap maturing in 2019 |  |  |  |
Swap Contracts |  |  |  |
Notional value |  | R$ 230,500 |  |
Amount receivable |  | R$ 30,249 |  |
Currency swap | Currency swap maturing in 2019 | CDI |  |  |  |
Swap Contracts |  |  |  |
Floating interest rate (as a percent) | 111.50% | 111.50% | 111.50% | 111.50%
Interest Rate Swap | Interest rate swap maturing in 2020 |  |  |  |
Swap Contracts |  |  |  |
Notional value |  | R$ 50,000 |  |
Amount receivable |  | R$ 2,706 |  |
Interest Rate Swap | Interest rate swap maturing in 2020 | CDI |  |  |  |
Swap Contracts |  |  |  |
Floating interest rate (as a percent) | 111.50% | 111.50% | 111.50% | 111.50%

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