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Risk Management And Derivatives: Utilities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) MMBTU mW	Dec. 31, 2020 MMBTU mW
Derivative [Line Items]
Collateral Already Posted, Aggregate Fair Value | $	$ 2,100
Natural Gas, Distribution | Future
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	590,000	620,000
Derivative, Remaining Maturity	3 months	3 months
Natural Gas, Distribution | Commodity Option
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	3,100,000	3,160,000
Derivative, Remaining Maturity	3 months	3 months
Natural Gas, Distribution | Basis Swap
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	870,000	900,000
Derivative, Remaining Maturity	3 months	3 months
Natural Gas, Distribution | Fixed for Float Swaps Purchased
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	4,570,000	3,850,000
Derivative, Remaining Maturity	34 months	17 months
Natural Gas, Distribution | Fixed for Float Swaps Purchased | Cash Flow Hedging | Over the Counter
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	1,830,000
Natural Gas, Distribution | Natural Gas Physical Purchases
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount	16,416,677	17,513,061
Derivative, Remaining Maturity	24 months	22 months
Electricity | Energy Related Derivative
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | mW	0	219,000
Derivative, Remaining Maturity	0 months	12 months

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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