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Fair Value Measurements: Schedule of Fair Values (Details) - USD ($) $ in Thousands | Mar. 31, 2022 | Dec. 31, 2021
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ContractSubjecttoMasterNetting |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Asset, Fair Value, Gross Asset | $ 0 | $ 2,400
Derivative Liability, Fair Value, Gross Liability | 0 | 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 | 0 | (2,374)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset | 0 | (1,814)
Fair Value, Measurements, Recurring | Fair Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative Assets, Total | 7,989 | 5,195
Derivative Liabilities, Total | 220 | 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 | 7,989 | 7,569
Derivative Liabilities, Total | 220 | 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 | 0 | (2,374)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset | 0 | (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, Commodity Derivatives | 7,989 | 5,195
Derivative Liabilities, Fair Value Disclosure | 220 | 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, Commodity Derivatives | 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, Commodity Derivatives | 7,989 | 7,569
Derivative Liabilities, Fair Value Disclosure | 220 | 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, Commodity Derivatives | 0 | 0
Derivative Liabilities, Fair Value Disclosure | $ 0 | $ 0

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