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Fair Value Measurements: Schedule of Fair Values (Details) - USD ($) | Jun. 30, 2023 | Dec. 31, 2022
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Asset, Statement of Financial Position [Extensible Enumeration] | Derivative Asset, Current | Derivative Asset, Current
Derivative Liability, Statement of Financial Position [Extensible Enumeration] | Derivative Liability, Current | Derivative Liability, Current
Contract Subject to Master Netting |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Asset, Fair Value, Gross Asset | $ 800,000 | $ 4,300,000
Derivative Liability, Fair Value, Gross Liability | 0 | 4,800,000
Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset | (751,000) | (4,290,000)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset | (25,000) | (4,837,000)
Fair Value, Measurements, Recurring | Fair Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Total | 303,000 | 1,117,000
Derivative Liabilities, Total | 470,000 | 6,618,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Total | 0 | 0
Derivative Liabilities, Total | 0 | 0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Total | 1,054,000 | 5,407,000
Derivative Liabilities, Total | 495,000 | 11,455,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Total | 0 | 0
Derivative Liabilities, Total | 0 | 0
Fair Value, Measurements, Recurring | Gas Utilities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Asset, Fair Value, Gross Liability and Obligation to Return Cash, Offset | (751,000) | (4,290,000)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset | (25,000) | (4,837,000)
Fair Value, Measurements, Recurring | Gas Utilities | Fair Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Fair Value Disclosure | 303,000 | 1,117,000
Derivative, Liabilities, Fair Value Disclosure | 470,000 | 6,618,000
Fair Value, Measurements, Recurring | Gas Utilities | Fair Value, Inputs, Level 1 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Fair Value Disclosure | 0 | 0
Derivative, Liabilities, Fair Value Disclosure | 0 | 0
Fair Value, Measurements, Recurring | Gas Utilities | Fair Value, Inputs, Level 2 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Fair Value Disclosure | 1,054,000 | 5,407,000
Derivative, Liabilities, Fair Value Disclosure | 495,000 | 11,455,000
Fair Value, Measurements, Recurring | Gas Utilities | Fair Value, Inputs, Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Fair Value Disclosure | 0 | 0
Derivative, Liabilities, Fair Value Disclosure | $ 0 | $ 0

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