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Commitments and Guarantees Schdule of Long term contracts for purchase of electric power (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 USD ($) MW | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Priest Rapids and Wanapum [Member] |  |  |
Long-term Contract for Purchase of Electric Power [Line Items] |  |  |
Revenue Bonds issued by the Public Utility Districts | $ 1,880 |  |
PGE Share of Output | 8.60% |  |
PGE Share of Capacity | MW | 163 |  |
commitment costs | $ 25 | $ 21 | $ 17
Wells [Member] |  |  |
Long-term Contract for Purchase of Electric Power [Line Items] |  |  |
Revenue Bonds issued by the Public Utility Districts | $ 572 |  |
PGE Share of Output | 16.60% |  |
PGE Share of Capacity | MW | 94 |  |
commitment costs | $ 23 | $ 16 | $ 11

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- Definition Revenue Bonds issued by the Public Utility Districts + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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