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Summary of Significant Accounting Policies Estimated average service lives (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($)
Generation, excluding thermal: |
Hydro | 99
Wind | 30
Transmission | 59
Distribution | 46
General | 12
Land, Buildings and Improvements [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment, Gross | $ 131

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- Definition estimated average service life - hydro production plant + References No definition available. + Details
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- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Details
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