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v3.21.1

Derivative financial instruments (Details 2) - Oil Swaps [Member] - 2020 [Member] | Dec. 31, 2020 USD ($) $ / shares
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First quarter [Member] |
Volume (Bbl) | $ | $ 15,255
Price per Bbl | $ / shares | $ 49.40
Second quarter [Member] |
Volume (Bbl) | $ | $ 15,180
Price per Bbl | $ / shares | $ 50.87
Third quarter [Member] |
Volume (Bbl) | $ | $ 5,200
Price per Bbl | $ / shares | $ 38.25
Fourth quarter [Member] |
Volume (Bbl) | $ | $ 0
Price per Bbl | $ / shares | $ 0.0

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