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Risk Management and Derivatives: Utilities (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2023 USD ($) MMBTU | Dec. 31, 2022 MMBTU
Derivative [Line Items] |  |  |
Credit Risk Derivative Liabilities, at Fair Value | $ |  | $ 0.6 |
Natural Gas, Distribution | Cash Flow Hedging |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount |  | 574,800 |
Natural Gas, Distribution | Natural gas futures purchased |  |  |
Derivative [Line Items] |  |  |
Derivative, Remaining Maturity | [1] |  | 3 months
Natural Gas, Distribution | Natural gas futures purchased | Long |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount |  |  | 630,000
Natural Gas, Distribution | Natural gas options purchased, net |  |  |
Derivative [Line Items] |  |  |
Derivative, Remaining Maturity | [1] |  | 3 months
Natural Gas, Distribution | Natural gas options purchased, net | Long |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount |  |  | 1,790,000
Natural Gas, Distribution | Natural gas basis swaps purchased |  |  |
Derivative [Line Items] |  |  |
Derivative, Remaining Maturity | [1] |  | 3 months
Natural Gas, Distribution | Natural gas basis swaps purchased | Long |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount |  |  | 900,000
Natural Gas, Distribution | Natural gas over-the-counter swaps, net |  |  |
Derivative [Line Items] |  |  |
Derivative, Remaining Maturity | [1],[2] | 26 months | 24 months
Natural Gas, Distribution | Natural gas over-the-counter swaps, net | Long |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount | [2] | 3,270,000 | 4,460,000
Natural Gas, Distribution | Natural gas physical contracts, net |  |  |
Derivative [Line Items] |  |  |
Derivative, Remaining Maturity | [1],[3] | 12 months | 12 months
Natural Gas, Distribution | Natural gas physical contracts, net | Long |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount | [3] | 3,881,190 | 17,864,412
[1] | Term reflects the maximum forward period hedged.
[2] | As of March 31, 2023, 574,800 MMBtus of natural gas over-the-counter swaps purchases were designated as cash flow hedges.
[3] | Volumes exclude derivative contracts that qualify for the normal purchases and normal sales exception permitted by GAAP.

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