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These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. false 71 Cash flow hedge, statement of income (loss) line item 2 us-gaap_GainLossOnCashFlowHedgesCaption us-gaap true na duration No definition available. false false false false false false false false false false false terselabel false 1 false false false false 0 0 Fuel and purchased energy expense false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false xbrli:stringItemType string Identifies the line item(s) where the net gain (loss) on cash flow hedges is reported in the statement of income or other statement of financial performance. Includes description for amounts included in other comprehensive income. 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