Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount of increase in the fair value of derivatives recognized in the income statement.

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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Risk Management and Derivatives: Derivatives Not Designated as Hedge Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Derivative [Line Items]
Regulatory assets	$ 702,368		$ 702,368		$ 796,599
Gas price derivatives
Derivative [Line Items]
Regulatory assets	4,845		4,845		$ 2,584
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(2,332)	$ (1,782)	1,162	$ (2,940)
Not Designated as Hedging Instrument \| Fuel, purchased power and cost of natural gas sold \| Electricity
Derivative [Line Items]
Derivative, Loss on Derivative	0	3,598	0	5,122
Not Designated as Hedging Instrument \| Fuel, purchased power and cost of natural gas sold \| Natural Gas
Derivative [Line Items]
Derivative, Loss on Derivative	$ 2,332
Derivative, Gain on Derivative		$ 1,816	$ 1,162	$ 2,182