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Derivative instruments - Impact of Derivatives on the Balance Sheet and Income Statement (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Derivative instruments |  |  |  |  |
Derivative assets, current portion | $ 4,376 |  | $ 4,376 |  |
Derivative assets, noncurrent portion | 812 |  | 812 |  |
Derivative liabilities, current portion | (3,941) |  | (3,941) |  | $ (3,953)
Derivative liabilities, noncurrent portion |  |  |  |  | (400)
Change in unrealized gain/(loss) on derivatives |  |  | 5,600 | $ (11,010) |
Total gain/(loss) on derivative contracts | 6,082 | $ (6,558) | (19,147) | (18,115) |
Primary underlying risk, Commodity Price | Non-hedging derivative instruments |  |  |  |  |
Derivative instruments |  |  |  |  |
Derivative assets, current portion | 4,376 |  | 4,376 |  |
Derivative assets, noncurrent portion | 812 |  | 812 |  |
Derivative liabilities, current portion | (3,941) |  | (3,941) |  | (3,953)
Derivative liabilities, noncurrent portion |  |  |  |  | (400)
Realized loss on derivatives | (9,331) | (3,959) | (24,747) | (7,105) |
Change in unrealized gain/(loss) on derivatives | 15,413 | (2,599) | 5,600 | (11,010) |
Total gain/(loss) on derivative contracts | 6,082 | (6,558) | (19,147) | (18,115) |
Crude oil | Primary underlying risk, Commodity Price | Non-hedging derivative instruments |  |  |  |  |
Derivative instruments |  |  |  |  |
Derivative assets, current portion | 4,581 |  | 4,581 |  |
Derivative assets, noncurrent portion | 812 |  | 812 |  |
Derivative liabilities, current portion | (1,865) |  | (1,865) |  | (3,465)
Derivative liabilities, noncurrent portion |  |  |  |  | (411)
Realized loss on derivatives | (4,971) | (2,324) | (15,388) | (2,583) |
Change in unrealized gain/(loss) on derivatives | 16,571 | 721 | 7,404 | (6,775) |
Total gain/(loss) on derivative contracts | 11,600 | (1,603) | (7,984) | (9,358) |
Natural gas | Primary underlying risk, Commodity Price | Non-hedging derivative instruments |  |  |  |  |
Derivative instruments |  |  |  |  |
Derivative assets, current portion | (205) |  | (205) |  |
Derivative liabilities, current portion | (2,076) |  | (2,076) |  | (488)
Derivative liabilities, noncurrent portion |  |  |  |  | $ 11
Realized loss on derivatives | (4,360) | (1,635) | (9,359) | (4,522) |
Change in unrealized gain/(loss) on derivatives | (1,158) | (3,320) | (1,804) | (4,235) |
Total gain/(loss) on derivative contracts | $ (5,518) | $ (4,955) | $ (11,163) | $ (8,757) |

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