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Energy Purchase Contracts (PUD Contracts Expenses) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($)
P U D Contracts Expenses [Abstract] |
Long-term contract for purchase of electric power, amount of long-term debt or lease obligation outstanding | $ 63.7

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- Definition PUD Contracts Expenses [Abstract] + References No definition available. + Details
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Period Type: | duration

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- Definition Under long-term contracts with public utility districts, cooperatives or other organizations, a utility company receives a portion of the output of a production plant constructed and financed by the district or cooperative. The utility has only a nominal or no investment at all in the plant but pays a proportionate part of the plant's costs, including debt service. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 10.D) -URI http://asc.fasb.org/extlink&oid=6499423&loc=d3e659339-123030 + Details
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