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Risk Management and Derivatives: Utilities (Details) $ in Millions | Sep. 30, 2025 USD ($) MMBTU | Dec. 31, 2024 MMBTU
--- | --- | ---
Derivative [Line Items] |  |  |
Credit Risk Derivative Liabilities, at Fair Value | $ |  | $ 0.8 |
Natural Gas, Distribution | Cash Flow Hedging |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount |  | 2,805,000 |
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 |  | 1,760,000 | 660,000
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 |  | 7,670,000 | 2,780,000
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 |  | 1,760,000 | 1,080,000
Natural Gas, Distribution | Natural gas over-the-counter swaps, net |  |  |
Derivative [Line Items] |  |  |
Derivative, Remaining Maturity | [1],[2] | 26 years | 20 years
Natural Gas, Distribution | Natural gas over-the-counter swaps, net | Long |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount | [2] | 4,810,000 | 3,480,000
Natural Gas, Distribution | Natural gas physical contracts, net |  |  |
Derivative [Line Items] |  |  |
Derivative, Remaining Maturity | [1],[3] | 6 years | 10 years
Natural Gas, Distribution | Natural gas physical contracts, net | Long |  |  |
Derivative [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount | [3] | 24,513,400 | 20,276,230
[1] | Term reflects the maximum forward period hedged.
[2] | As of September 30, 2025, 2,805,000 MMBtus of natural gas over-the-counter swaps purchases were designated as cash flow hedges.
[3] | Volumes exclude contracts that qualify for the normal purchases and normal sales exception under GAAP.

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