Fair Value Measurements: Recurring Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Contract Subject to Master Netting Arrangement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 2,400	$ 1,500
Derivative Liability, Fair Value, Gross Liability	1,800	1,600
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	(2,374)	(1,527)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(1,814)	(1,552)
Fair Value, Measurements, Recurring \| Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Total	5,195	2,042
Derivative Liabilities, Total	1,459	2,044
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	7,569	3,569
Derivative Liabilities, Total	3,273	3,596
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	(2,374)	(1,527)
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	(1,814)	(1,552)
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	5,195	977
Derivative, Liabilities, Fair Value Disclosure	1,459	1,123
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	7,569	2,504
Derivative, Liabilities, Fair Value Disclosure	3,273	2,675
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
Fair Value, Measurements, Recurring \| Electric 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
Derivative Liability, Fair Value, Gross Asset and Right to Reclaim Cash, Offset	0	0
Fair Value, Measurements, Recurring \| Electric Utilities \| Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0	1,065
Derivative, Liabilities, Fair Value Disclosure	0	921
Fair Value, Measurements, Recurring \| Electric 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
Derivative, Liabilities, Fair Value Disclosure		0
Fair Value, Measurements, Recurring \| Electric Utilities \| Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets, Fair Value Disclosure	0	1,065
Derivative, Liabilities, Fair Value Disclosure	0	921
Fair Value, Measurements, Recurring \| Electric 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
Derivative, Liabilities, Fair Value Disclosure		$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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