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Regulatory Matters - Schedule of Decoupling and Earnings Sharing Mechanisms (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
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WASHINGTON | Decoupling Surcharge [Member] |  |
Scheduleof Decouplingand Earnings Sharing [Line Items] |  |
Regulatory assets | $ 21,340,000 | $ 22,440,000
WASHINGTON | Revenue Subject to Refund [Member] |  |
Scheduleof Decouplingand Earnings Sharing [Line Items] |  |
Regulatory Liabilities | 0 | 0
IDAHO | Decoupling Surcharge [Member] |  |
Scheduleof Decouplingand Earnings Sharing [Line Items] |  |
Regulatory assets | 1,202,000 | 2,549,000
IDAHO | Revenue Subject to Refund [Member] |  |
Scheduleof Decouplingand Earnings Sharing [Line Items] |  |
Regulatory Liabilities | (686,000) | (686,000)
OREGON | Revenue Subject to Refund [Member] |  |
Scheduleof Decouplingand Earnings Sharing [Line Items] |  |
Regulatory Liabilities | 0 | 0
OREGON | Decoupling Surcharge [Member] |  |
Scheduleof Decouplingand Earnings Sharing [Line Items] |  |
Regulatory Liabilities | $ (1,262,000) | $ (739,000)

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- Definition 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 + Details
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