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Risk Management and Derivatives: Utilities (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2022 USD ($) MMBTU | Dec. 31, 2021 MMBTU
Derivative [Line Items] |  |
Credit Risk Derivative Liabilities, at Fair Value | $ | $ 0.3 |
Natural Gas, Distribution | Cash Flow Hedging |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 410,000 |
Natural Gas, Distribution | Natural gas futures purchased |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 0 months | 3 months
Natural Gas, Distribution | Natural gas futures purchased | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 0 | 590,000
Natural Gas, Distribution | Natural gas options purchased, net |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 0 months | 3 months
Natural Gas, Distribution | Natural gas options purchased, net | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 0 | 3,100,000
Natural Gas, Distribution | Natural gas basis swaps purchased |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 0 months | 3 months
Natural Gas, Distribution | Natural gas basis swaps purchased | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 0 | 870,000
Natural Gas, Distribution | Natural gas over-the-counter swaps, net |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 33 months | 34 months
Natural Gas, Distribution | Natural gas over-the-counter swaps, net | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 2,750,000 | 4,570,000
Natural Gas, Distribution | Natural gas physical contracts, net |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 21 months | 24 months
Natural Gas, Distribution | Natural gas physical contracts, net | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 4,181,531 | 16,416,677

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