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Risk Management and Derivatives: Utilities (Details) $ in Millions | Sep. 30, 2024 USD ($) MMBTU | Dec. 31, 2023 MMBTU
--- | --- | ---
Derivative [Line Items] |  |  |  |
Credit Risk Derivative Liabilities, at Fair Value | $ |  | $ 0.5 |  |
Natural Gas, Distribution | Cash Flow Hedging |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount |  | 2,276,000 |  |
Natural Gas, Distribution | Natural gas futures purchased |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Remaining Maturity | [1] | 6 months | 3 months |
Natural Gas, Distribution | Natural gas futures purchased | Long |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount |  | 1,800,000 | 650,000 |
Natural Gas, Distribution | Natural gas options purchased, net |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Remaining Maturity | [1] | 6 months | 3 months |
Natural Gas, Distribution | Natural gas options purchased, net | Long |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount |  | 7,680,000 | 2,850,000 |
Natural Gas, Distribution | Natural gas basis swaps purchased |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Remaining Maturity | [1] | 6 months | 3 months |
Natural Gas, Distribution | Natural gas basis swaps purchased | Long |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount |  | 1,800,000 | 1,050,000 |
Natural Gas, Distribution | Natural gas over-the-counter swaps, net |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Remaining Maturity | [1] | 22 months | 21 months | [2]
Natural Gas, Distribution | Natural gas over-the-counter swaps, net | Long |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount | [2] | 4,890,000 | 3,890,000 |
Natural Gas, Distribution | Natural gas physical contracts, net |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Remaining Maturity | [1] | 6 months | 10 months | [3]
Natural Gas, Distribution | Natural gas physical contracts, net | Long |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, Nonmonetary Notional Amount | [3] | 32,240,665 | 12,582,415 |
[1] | Term reflects the maximum forward period hedged.
[2] | As of September 30, 2024, 2,276,000 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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