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Summary of Significant Accounting Policies Estimated average service lives (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Generation, excluding thermal: |  |
Hydro | 97 years |
Wind | 30 years |
Transmission | 61 years |
Distribution | 51 years |
General | 16 years |
Other Investments | $ 150 | $ 44

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