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Summary of Significant Accounting Policies Estimated average service lives (Details) | 12 Months Ended
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Dec. 31, 2020
Generation, excluding thermal: |
Hydro | 97 years
Wind | 31 years
Transmission | 58 years
Distribution | 46 years
General | 13 years

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- Definition estimated average service life - hydro production plant + References No definition available. + Details
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- Definition estimated average service life - wind production plant + References No definition available. + Details
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- Definition Useful life of assets common to business units owned by public utility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Useful life of utility distribution assets owned by public utility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Useful life of utility transmission equipment owned by public utility, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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