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v3.19.1

Derivative financial instruments - Forward Contracts, Fuel Oil, Gas Oil, Diesel Narrative (Details) l in Thousands, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 USD ($) l | Dec. 31, 2017 USD ($) | Mar. 12, 2019 $ / l l
Disclosure of detailed information about financial instruments [line items] |  |  |
Unrealized (loss) gain on derivative instruments (Note 14) | $ | $ (4,757) | $ 9,684 |
Fuel derivative contracts |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Unrealized (loss) gain on derivative instruments (Note 14) | $ | (9,000) | $ 5,000 |
Forward contracts | Fuel derivative contracts |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Financial assets, at fair value | $ | $ (2,000) |  |
Forward contracts | Not Designated As Hedging Instrument | Forward – fuel oil: |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Forward fuel contracts | 25,201 |  |
Forward contracts | Not Designated As Hedging Instrument | Forward – gas oil: |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Forward fuel contracts | 10,828 |  |
Forward contracts | Not Designated As Hedging Instrument | Forward – diesel: |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Forward fuel contracts | 3,009 |  |
Entering into significant commitments or contingent liabilities | Forward contracts | Forward – fuel oil: |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Average price per litre (in usd per litre) | $ / l |  |  | 0.28
Entering into significant commitments or contingent liabilities | Forward contracts | Forward – gas oil: |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Average price per litre (in usd per litre) | $ / l |  |  | 0.49
Entering into significant commitments or contingent liabilities | Forward contracts | Not Designated As Hedging Instrument | Forward – fuel oil: |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Forward fuel contracts |  |  | 19,202
Entering into significant commitments or contingent liabilities | Forward contracts | Not Designated As Hedging Instrument | Forward – gas oil: |  |  |
Disclosure of detailed information about financial instruments [line items] |  |  |
Forward fuel contracts |  |  | 24,852

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