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Fair Value Measurements: Schedule of Fair Values (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
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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 | $ 4,300 | $ 2,400
Derivative Liability, Fair Value, Gross Liability | 4,800 | 1,800
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 | (4,290) | (2,374)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset | (4,837) | (1,814)
Fair Value, Measurements, Recurring | Fair Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Total | 1,117 | 5,195
Derivative Liabilities, Total | 6,618 | 1,459
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 | 5,407 | 7,569
Derivative Liabilities, Total | 11,455 | 3,273
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 | (4,290) | (2,374)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset | (4,837) | (1,814)
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 | 1,117 | 5,195
Derivative, Liabilities, Fair Value Disclosure | 6,618 | 1,459
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 | 5,407 | 7,569
Derivative, Liabilities, Fair Value Disclosure | 11,455 | 3,273
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

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