Regulatory Matters - Schedule of Decoupling and Earnings Sharing Mechanisms (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
WASHINGTON \| Decoupling Surcharge (Rebate) [Member]
Scheduleof Decouplingand Earnings Sharing [Line Items]
Regulatory assets	$ 13,522,000	$ 21,340,000
WASHINGTON \| Revenue Subject to Refund [Member]
Scheduleof Decouplingand Earnings Sharing [Line Items]
Regulatory Liabilities	0	0
IDAHO \| Decoupling Surcharge (Rebate) [Member]
Scheduleof Decouplingand Earnings Sharing [Line Items]
Regulatory assets		1,202,000
IDAHO \| Revenue Subject to Refund [Member]
Scheduleof Decouplingand Earnings Sharing [Line Items]
Regulatory Liabilities	(686,000)	(686,000)
IDAHO \| Decoupling Surcharge (Rebate) [Member]
Scheduleof Decouplingand Earnings Sharing [Line Items]
Regulatory Liabilities	(1,450,000)
OREGON \| Revenue Subject to Refund [Member]
Scheduleof Decouplingand Earnings Sharing [Line Items]
Regulatory Liabilities	0	0
OREGON \| Decoupling Surcharge (Rebate) [Member]
Scheduleof Decouplingand Earnings Sharing [Line Items]
Regulatory Liabilities	$ (3,152,000)	$ (1,262,000)

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 405
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394

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