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Risk Management and Derivatives: Utilities (Details) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) mW MMBTU | Dec. 31, 2020 MMBTU mW
Commodity Contract |  |
Derivative [Line Items] |  |
Credit Risk Derivative Liabilities, at Fair Value | $ | $ 0.9 |
Natural Gas, Distribution | Cash Flow Hedging |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 2,700,000 |
Natural Gas, Distribution | Natural gas futures purchased |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 6 months | 3 months
Natural Gas, Distribution | Natural gas futures purchased | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 1,700,000 | 620,000
Natural Gas, Distribution | Natural gas options purchased, net |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 6 months | 3 months
Natural Gas, Distribution | Natural gas options purchased, net | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 8,420,000 | 3,160,000
Natural Gas, Distribution | Natural gas basis swaps purchased |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 6 months | 3 months
Natural Gas, Distribution | Natural gas basis swaps purchased | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 1,500,000 | 900,000
Natural Gas, Distribution | Natural gas over-the-counter swaps, net |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 35 months | 17 months
Natural Gas, Distribution | Natural gas over-the-counter swaps, net | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 5,920,000 | 3,850,000
Natural Gas, Distribution | Natural gas physical contracts, net |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 7 months | 22 months
Natural Gas, Distribution | Natural gas physical contracts, net | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | 18,758,835 | 17,513,061
Electricity | Electric wholesale contracts |  |
Derivative [Line Items] |  |
Derivative, Remaining Maturity | 3 months | 12 months
Electricity | Electric wholesale contracts | Long |  |
Derivative [Line Items] |  |
Derivative, Nonmonetary Notional Amount | mW | 65,625 | 219,000

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