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Element us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1 had a mix of decimals attribute values: -6 -3. Element us-gaap_PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress had a mix of decimals attribute values: -7 -5. Element us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService had a mix of decimals attribute values: 0 3. Element us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDistribution had a mix of decimals attribute values: -6 -3. Element us-gaap_PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing had a mix of decimals attribute values: -6 -3. Element us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInService had a mix of decimals attribute values: -6 -3. Element us-gaap_PublicUtilitiesPropertyPlantAndEquipmentTransmission had a mix of decimals attribute values: -6 -3. Element us-gaap_RecordedUnconditionalPurchaseObligation had a mix of decimals attribute values: -6 -5. Element us-gaap_RecordedUnconditionalPurchaseObligationDueAfterFifthYear had a mix of decimals attribute values: -6 -5. Element us-gaap_RecordedUnconditionalPurchaseObligationDueInFifthYear had a mix of decimals attribute values: -6 -5. Element us-gaap_RecordedUnconditionalPurchaseObligationDueInFourthYear had a mix of decimals attribute values: -6 -5. Element us-gaap_RecordedUnconditionalPurchaseObligationDueInSecondYear had a mix of decimals attribute values: -6 -5. Element us-gaap_RecordedUnconditionalPurchaseObligationDueInThirdYear had a mix of decimals attribute values: -6 -5. Element us-gaap_RecordedUnconditionalPurchaseObligationDueWithinOneYear had a mix of decimals attribute values: -6 -5. Element us-gaap_RegulatoryAssets had a mix of decimals attribute values: -6 -5. Element us-gaap_RelatedPartyTransactionAmountsOfTransaction had a mix of decimals attribute values: -6 -5. Element us-gaap_RepaymentsOfOtherLongTermDebt had a mix of decimals attribute values: -6 -3. Element us-gaap_RepaymentsOfPollutionControlBond had a mix of decimals attribute values: -6 -3. Element us-gaap_RepaymentsOfSeniorDebt had a mix of decimals attribute values: -6 -3. Element us-gaap_RetainedEarningsAccumulatedDeficit had a mix of decimals attribute values: -6 -3. Element us-gaap_Revenues had a mix of decimals attribute values: -6 -3. Element us-gaap_SeniorNotes had a mix of decimals attribute values: -8 -6 0. Element us-gaap_SeniorNotesCurrent had a mix of decimals attribute values: -6 -5. Element us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1 had a mix of decimals attribute values: -6 -5. Element us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue had a mix of decimals attribute values: -6 -5. Element us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue had a mix of decimals attribute values: -6 -5. Element us-gaap_ShortTermBorrowings had a mix of decimals attribute values: -6 -3. Element us-gaap_StateAndLocalIncomeTaxExpenseBenefitContinuingOperations had a mix of decimals attribute values: -6 -3. Element us-gaap_StockholdersEquity had a mix of decimals attribute values: -6 -3. Element us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest had a mix of decimals attribute values: -6 -3. Element us-gaap_StockholdersEquityOther had a mix of decimals attribute values: -6 -3. Element us-gaap_StockIssuedDuringPeriodValueNewIssues had a mix of decimals attribute values: -6 -3. Element us-gaap_StockOptionPlanExpense had a mix of decimals attribute values: -6 -3. Element us-gaap_TaxCreditCarryforwardAmount had a mix of decimals attribute values: -6 -5. Element us-gaap_TaxesExcludingIncomeAndExciseTaxes had a mix of decimals attribute values: -6 -3. Element us-gaap_UnrecognizedTaxBenefits had a mix of decimals attribute values: -6 -3. Element us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions had a mix of decimals attribute values: -6 -3. Element us-gaap_UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities had a mix of decimals attribute values: -6 -3. Element us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions had a mix of decimals attribute values: -6 -3. Element us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions had a mix of decimals attribute values: -6 -3. Element us-gaap_UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate had a mix of decimals attribute values: -6 -3. Element us-gaap_UtilitiesOperatingExpenseFuelUsed had a mix of decimals attribute values: -6 -3. Element us-gaap_UtilitiesOperatingExpenseMaintenanceAndOperations had a mix of decimals attribute values: -6 -3. 'Monetary' elements on report '1001000 - Statement - Consolidated Statements of Income' had a mix of different decimal attribute values. 'Monetary' elements on report '1002000 - Statement - Consolidated Statements of Comprehensive Income' had a mix of different decimal attribute values. 'Monetary' elements on report '1002501 - Statement - Consolidated Statements of Comprehensive Income (Parenthetical)' had a mix of different decimal attribute values. Columns in Cash Flows statement 'Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 282 values. Shorter duration columns must have at least one fourth (70) as many values. Column '1/1/2014 - 1/31/2014' is shorter (30 days) and has only 7 values, so it is being removed. 'Monetary' elements on report '1003000 - Statement - Consolidated Statements of Cash Flows' had a mix of different decimal attribute values. 'Monetary' elements on report '1004000 - Statement - Consolidated Balance Sheets' had a mix of different decimal attribute values. 'Monetary' elements on report '1005000 - Statement - Consolidated Statements of Capitalization' had a mix of different decimal attribute values. 'Monetary' elements on report '1006000 - Statement - Consolidated Statements of Common Stockholders Equity' had a mix of different decimal attribute values. 'Monetary' elements on report '2401403 - Disclosure - Summary of Significant Accounting Policies - Regulatory Assets and Liabilities (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2401404 - Disclosure - Summary of Significant Accounting Policies - Property, Plant, and Equipment (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2401415 - Disclosure - Summary of Significant Accounting Policies - Textual (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2402407 - Disclosure - Retirement Benefits - Components of Accumulated OCI and Changes in Regulatory Assets (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2402412 - Disclosure - Retirement Benefits - Textual (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2404402 - Disclosure - Contingencies and Regulatory Matters - Current And Actual Cost Estimate (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2404403 - Disclosure - Contingencies and Regulatory Matters - Textual (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2405402 - Disclosure - Joint Ownership Agreements (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2406403 - Disclosure - Income Taxes - Deferred Tax Assets and Liabilities (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2406405 - Disclosure - Income Taxes - Changes in Unrecognized Tax Benefits (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2406408 - Disclosure - Income Taxes - Textual (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2407402 - Disclosure - Financing - Scheduled Maturities and Redemptions of Securities Due Within One Year (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2407404 - Disclosure - Financing - Short-term Borrowings (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2407405 - Disclosure - Financing - Textual (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2408402 - Disclosure - Commitments - Estimated Long-term obligations (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2408403 - Disclosure - Commitments (Details)' had a mix of different decimal attribute values. 'Shares' elements on report '2409405 - Disclosure - Common Stock and Stock Compensation - Textual (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2409405 - Disclosure - Common Stock and Stock Compensation - Textual (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2410401 - Disclosure - Nuclear Insurance (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2411403 - Disclosure - Fair Value Measurements - Fair Value, Nature and Risk of Investments (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2412403 - Disclosure - Derivatives - Financial Statement Presentation (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2413402 - Disclosure - Segment and Related Information - Financial Data for Business Segments and Products and Services (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2414402 - Disclosure - Noncontrolling Interest (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2414403 - Disclosure - Noncontrolling Interest - Net Income (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2415402 - Disclosure - Quarterly Financial Information (Unaudited) (Details)' had a mix of different decimal attribute values. Process Flow-Through: 1001000 - Statement - Consolidated Statements of Income Process Flow-Through: Removing column '3 Months Ended Dec. 31, 2014' Process Flow-Through: Removing column '3 Months Ended Sep. 30, 2014' Process Flow-Through: Removing column '3 Months Ended Jun. 30, 2014' Process Flow-Through: Removing column '3 Months Ended Mar. 31, 2014' Process Flow-Through: Removing column '3 Months Ended Dec. 31, 2013' Process Flow-Through: Removing column '3 Months Ended Sep. 30, 2013' Process Flow-Through: Removing column '3 Months Ended Jun. 30, 2013' Process Flow-Through: Removing column '3 Months Ended Mar. 31, 2013' Process Flow-Through: 1002000 - Statement - Consolidated Statements of Comprehensive Income Process Flow-Through: 1002501 - Statement - Consolidated Statements of Comprehensive Income (Parenthetical) Process Flow-Through: 1003000 - Statement - Consolidated Statements of Cash Flows Process Flow-Through: 1003501 - Statement - Consolidated Statements of Cash Flows (Parenthetical) Process Flow-Through: 1004000 - Statement - Consolidated Balance Sheets Process Flow-Through: Removing column 'Dec. 31, 2012' Process Flow-Through: Removing column 'Dec. 31, 2011' Process Flow-Through: 1004501 - Statement - Consolidated Balance Sheets (Parenthetical) Process Flow-Through: 1005000 - Statement - Consolidated Statements of Capitalization Process Flow-Through: Removing column 'Dec. 31, 2012' Process Flow-Through: Removing column 'Dec. 31, 2011' Process Flow-Through: 1005501 - Statement - Consolidated Statements of Capitalization (Parenthetical) Process Flow-Through: Removing column 'Jan. 31, 2014' Process Flow-Through: Removing column 'Dec. 31, 2012' Process Flow-Through: Removing column 'Dec. 31, 2011' so-20141231.xml so-20141231.xsd so-20141231_cal.xml so-20141231_def.xml so-20141231_lab.xml so-20141231_pre.xml true true