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Disclosure - Revision of Previously Issued Financial Statements - Schedule of Effects of the Prior-Period Errors on the Consolidated Balance Sheets (Details) link:presentationLink link:calculationLink link:definitionLink 9955532 - Disclosure - Revision of Previously Issued Financial Statements - Schedule of Effects of the Prior-Period Errors on the Consolidated Statements of Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955533 - Disclosure - Revision of Previously Issued Financial Statements - Schedule of Effects of the Prior-Period Errors on the Consolidated Statements of Comprehensive Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955534 - Disclosure - Revision of Previously Issued Financial Statements - Schedule of Effects of the Prior-Period Errors on the Consolidated Statements of Cash Flows (Details) link:presentationLink link:calculationLink link:definitionLink 9955535 - Disclosure - Revision of Previously Issued Financial Statements - Schedule of Effects of the Prior-Period Errors on the Consolidated Statements of Equity (Details) link:presentationLink link:calculationLink link:definitionLink 9955536 - Disclosure - Regulated Operations Plant - Schedule of Regulated Operations Plant (Details) link:presentationLink link:calculationLink link:definitionLink 9955537 - Disclosure - Regulated Operations Plant - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955538 - Disclosure - Regulated Operations Plant - Schedule of Depreciation and Amortization Expense (Details) link:presentationLink link:calculationLink link:definitionLink 9955539 - Disclosure - Regulatory Assets and Liabilities - Schedule of Regulatory Assets and Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 9955540 - Disclosure - Regulatory Assets and Liabilities - Schedule of Components of Other Regulatory Assets (Details) link:presentationLink link:calculationLink link:definitionLink 9955541 - 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Disclosure - Receivables and Related Allowances - Schedule of Percent of Customers by State (Details) link:presentationLink link:calculationLink link:definitionLink 9955548 - Disclosure - Receivables and Related Allowances - Schedule of Allowance for Uncollectibles (Details) link:presentationLink link:calculationLink link:definitionLink 9955549 - Disclosure - Common Stock (Details) link:presentationLink link:calculationLink link:definitionLink 9955550 - Disclosure - Debt - Schedule of Carrying Amounts and Estimated Fair Values of Long-Term Debt (Details) link:presentationLink link:calculationLink link:definitionLink 9955550 - Disclosure - Debt - Schedule of Carrying Amounts and Estimated Fair Values of Long-Term Debt (Details) link:presentationLink link:calculationLink link:definitionLink 9955551 - Disclosure - Debt - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955552 - Disclosure - Debt - Schedule of Effective Interest Rates on Variable-Rate IDRBs (Details) link:presentationLink link:calculationLink link:definitionLink 9955553 - Disclosure - Debt - Schedule of Estimated Maturities of Long-Term Debt (Details) link:presentationLink link:calculationLink link:definitionLink 9955554 - Disclosure - Pension and Other Postretirement Benefits - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955555 - Disclosure - Pension and Other Postretirement Benefits - Schedule of Asset Return Assumption (Details) link:presentationLink link:calculationLink link:definitionLink 9955556 - Disclosure - Pension and Other Postretirement Benefits - Schedule of Amounts Recognized in Balance Sheet and Income Statement (Details) link:presentationLink link:calculationLink link:definitionLink 9955557 - Disclosure - Pension and Other Postretirement Benefits - Schedule of Accumulated Benefit Obligation (Details) link:presentationLink link:calculationLink link:definitionLink 9955558 - Disclosure - Pension and Other Postretirement Benefits - Schedule of Expected Benefit Payments (Details) link:presentationLink link:calculationLink link:definitionLink 9955559 - Disclosure - Pension and Other Postretirement Benefits - Schedule of Net Periodic Benefit Cost and Weighted-Average Assumptions (Details) link:presentationLink link:calculationLink link:definitionLink 9955560 - Disclosure - Pension and Other Postretirement Benefits - Schedule of Other Changes in Plan Assets and Benefit Obligations Recognized in Net Periodic Benefit Cost and Other Comprehensive Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955561 - Disclosure - Pension and Other Postretirement Benefits - Schedule of Fair Value of Plan Assets (Details) link:presentationLink link:calculationLink link:definitionLink 9955562 - Disclosure - Income Taxes - Schedule of Income Before Taxes (Details) link:presentationLink link:calculationLink link:definitionLink 9955563 - Disclosure - Income Taxes - Schedule of Income Tax Expense (Benefit) (Details) link:presentationLink link:calculationLink link:definitionLink 9955564 - Disclosure - Income Taxes - Schedule of Reconciliation of U.S Federal Statutory Rate to Consolidated Effective Tax Rate (Details) link:presentationLink link:calculationLink link:definitionLink 9955565 - 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Schedule of Effects of the Prior-Period Errors on the Consolidated Balance Sheets (Details) link:presentationLink link:calculationLink link:definitionLink 9955579 - Disclosure - Previously Issued Condensed Consolidated Financial Statements (Unaudited) - Schedule of Effects of the Prior-Period Errors on the Consolidated Statements of Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955580 - Disclosure - Previously Issued Condensed Consolidated Financial Statements (Unaudited) - Schedule of Effects of the Prior-Period Errors on the Consolidated Statements of Comprehensive Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955581 - Disclosure - Previously Issued Condensed Consolidated Financial Statements (Unaudited) - Schedule of Effects of the Prior-Period Errors on the Consolidated Statements of Cash Flows (Details) link:presentationLink link:calculationLink link:definitionLink 9955582 - Disclosure - Previously Issued Condensed Consolidated Financial Statements (Unaudited) - 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