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Risk Management And Derivatives: Utilities (Details) $ in Thousands | 12 Months Ended
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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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