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Risk Management And Derivatives: Derivatives by Balance Sheet Classification (Details) - Commodity Contract - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Designated as Hedging Instrument
Fair Value Hedges, Net	$ 116	$ (515)
Not Designated as Hedging Instrument
Fair Value Hedges, Net	(118)	(1,484)
Derivative Assets, Current | Designated as Hedging Instrument
Fair Value Hedge Assets	181	1
Derivative Assets, Current | Not Designated as Hedging Instrument
Fair Value Hedge Assets	1,667	341
Derivative Assets, Noncurrent | Designated as Hedging Instrument
Fair Value Hedge Assets	43	3
Derivative Assets, Noncurrent | Not Designated as Hedging Instrument
Fair Value Hedge Assets	151	2
Derivative Liabilities, Current | Designated as Hedging Instrument
Derivative Liability, Current	(108)	(490)
Derivative Liabilities, Current | Not Designated as Hedging Instrument
Derivative Liability, Current	(1,936)	(1,764)
Derivative Liabilities, Noncurrent | Designated as Hedging Instrument
Derivative Liability, Current	0	(29)
Derivative Liabilities, Noncurrent | Not Designated as Hedging Instrument
Derivative Liability, Current	$ 0	$ (63)

X

- Definition

Fair value of all derivative assets designated as fair value hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624163-113959

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Fair value of all derivative liabilities designated as fair value hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
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Net fair value of all derivative instruments designated as fair value hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
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