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Risk Management And Derivatives: Derivatives by Balance Sheet Classification (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Designated as Hedging Instrument |  |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | $ 2,035 | $ 116
Commodity Contract | Not Designated as Hedging Instrument |  |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral | 1,701 | (118)
Derivative Assets, Current | Commodity Contract | Designated as Hedging Instrument |  |
Derivative Asset, Fair Value, Gross Asset | 2,017 | 181
Derivative Assets, Current | Commodity Contract | Not Designated as Hedging Instrument |  |
Derivative Asset, Fair Value, Gross Asset | 2,356 | 1,667
Derivative Assets, Noncurrent | Commodity Contract | Designated as Hedging Instrument |  |
Derivative Asset, Fair Value, Gross Asset | 18 | 43
Derivative Assets, Noncurrent | Commodity Contract | Not Designated as Hedging Instrument |  |
Derivative Asset, Fair Value, Gross Asset | 804 | 151
Derivative Liabilities, Current | Commodity Contract | Designated as Hedging Instrument |  |
Derivative Liability, Fair Value, Gross Liability | 0 | (108)
Derivative Liabilities, Current | Commodity Contract | Not Designated as Hedging Instrument |  |
Derivative Liability, Fair Value, Gross Liability | (1,439) | (1,936)
Derivative Liabilities, Noncurrent | Commodity Contract | Not Designated as Hedging Instrument |  |
Derivative Liability, Fair Value, Gross Liability | $ (20) | $ 0

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