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Property, Plant And Equipment Property, Plant and Equipment (Schedule of Depreciation Provisions For Utility Plant as a Percentage of the Original Cost) (Details) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Electric Operations |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciation Provisions For Utility Plant Percentage | 3.40% | 2.80% | 2.90%
Gas Distribution Operations |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciation Provisions For Utility Plant Percentage | 2.30% | 2.50% | 2.20%

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- Definition Depreciation provisions for utility plant percentage + 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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Namespace Prefix: |
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Balance Type: |
Period Type: |