| Current Federal Tax Expense (Benefit) | -209.00M | 2025-01-01 → 2025-12-31 |
| Current State and Local Tax Expense (Benefit) | 28.00M | 2025-01-01 → 2025-12-31 |
| Deferred Federal Income Tax Expense (Benefit) | 298.00M | 2025-01-01 → 2025-12-31 |
| Deferred State and Local Income Tax Expense (Benefit) | 12.00M | 2025-01-01 → 2025-12-31 |
| Inventory, Raw Materials, Gross | 576.00M | as of 2025-12-31 |
| Asset Retirement Obligation, Liabilities Incurred | 45.00M | 2025-01-01 → 2025-12-31 |
| Asset Retirement Obligation, Liabilities Settled | 103.00M | 2025-01-01 → 2025-12-31 |
| Operating Lease, Liability, Current | 100.00M | as of 2025-12-31 |
| Other Inventory, Supplies, Gross | 1.05B | as of 2025-12-31 |
| Asset Retirement Obligation, Revision of Estimate | -12.00M | 2025-01-01 → 2025-12-31 |
| Prepaid Expense and Other Assets, Current | 212.00M | as of 2025-12-31 |
| Federal Income Tax Expense (Benefit), Continuing Operations | 89.00M | 2025-01-01 → 2025-12-31 |
| State and Local Income Tax Expense (Benefit), Continuing Operations | 40.00M | 2025-01-01 → 2025-12-31 |
| Share-based Payment Arrangement, Amount Capitalized | 17.00M | 2025-01-01 → 2025-12-31 |
| SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount | 52.00M | as of 2025-12-31 |
| Share-based Payment Arrangement, Expense | 53.00M | 2025-01-01 → 2025-12-31 |
| SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense | 50.00M | 2025-01-01 → 2025-12-31 |
| SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account | 2.00M | 2025-01-01 → 2025-12-31 |
| SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction | 61.00M | 2025-01-01 → 2025-12-31 |
| Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity | 245.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount | 803.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount | 31.00M | 2025-01-01 → 2025-12-31 |
| Share-based Payment Arrangement, Expense, Tax Benefit | 8.00M | 2025-01-01 → 2025-12-31 |
| Long-term Debt, Fair Value | 44.93B | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Amount | 3.00M | 2025-01-01 → 2025-12-31 |
| EffectiveIncomeTaxRateReconciliationTaxCreditEnergyRelatedAmount | 244.00M | 2025-01-01 → 2025-12-31 |
| Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | 95.00M | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount | 4.00M | 2025-01-01 → 2025-12-31 |
| Derivative, Gain (Loss) on Derivative, Net | 42.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount | 0 | 2025-01-01 → 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Generation or Processing | 28.25B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Transmission | 42.56B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Distribution | 33.36B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Construction Work in Progress | 7.61B | as of 2025-12-31 |
| SegmentExpenditureAdditionToLongLivedAssets | 11.91B | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Contingency, Amount | 3.00M | 2025-01-01 → 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment | 7.73B | as of 2025-12-31 |
| SegmentReportingOtherItemAmount | -70.00M | 2025-01-01 → 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Accumulated Depreciation | 27.88B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Net | 91.64B | as of 2025-12-31 |
| Dividends, Common Stock | 2.01B | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Other Adjustments, Amount | 11.00M | 2025-01-01 → 2025-12-31 |
| Revenue, Remaining Performance Obligation, Amount | 226.00M | as of 2025-12-31 |
| Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service | 1.93B | as of 2025-12-31 |
| Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation | 589.00M | as of 2025-12-31 |
| Net Income (Loss) Available to Common Stockholders, Diluted | 3.58B | 2025-01-01 → 2025-12-31 |
| Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress | 3.00M | as of 2025-12-31 |
| Deferred Tax Assets, Operating Loss Carryforwards | 155.00M | as of 2025-12-31 |
| Stock Issued During Period, Value, New Issues | 775.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Tax Credit Carryforwards, General Business | 148.00M | as of 2025-12-31 |
| Operating Lease, Cost | 137.00M | 2025-01-01 → 2025-12-31 |
| Lease, Cost | 198.00M | 2025-01-01 → 2025-12-31 |
| Finance Lease, Liability, Payment, Due | 180.00M | as of 2025-12-31 |
| Finance Lease, Liability, Payments, Due in Next Rolling Twelve Months | 52.00M | as of 2025-12-31 |
| Finance Lease, Liability, Payments, Due in Rolling Year Two | 41.00M | as of 2025-12-31 |
| Finance Lease, Liability, Payments, Due in Rolling Year Three | 30.00M | as of 2025-12-31 |
| Finance Lease, Liability, Payments, Due in Rolling Year Four | 21.00M | as of 2025-12-31 |
| Finance Lease, Liability, Payments, Due in Rolling Year Five | 15.00M | as of 2025-12-31 |
| Finance Lease, Liability, Payments, Due in Rolling after Year Five | 21.00M | as of 2025-12-31 |
| Finance Lease, Liability, Undiscounted Excess Amount | 25.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid | 1.07B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, Payments, Due Next Rolling Twelve Months | 133.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, Payments, Due in Rolling Year Two | 114.00M | as of 2025-12-31 |
| Utilities Operating Expense, Maintenance | 1.50B | 2025-01-01 → 2025-12-31 |
| Lessee, Operating Lease, Liability, Payments, Due in Rolling Year Three | 99.00M | as of 2025-12-31 |
| Utilities Operating Expense, Operations | 2.95B | 2025-01-01 → 2025-12-31 |
| Lessee, Operating Lease, Liability, Payments, Due in Rolling Year Four | 71.00M | as of 2025-12-31 |
| Utilities Operating Expense, Maintenance and Operations | 4.45B | 2025-01-01 → 2025-12-31 |
| Lessee, Operating Lease, Liability, Payments, Due in Rolling Year Five | 47.00M | as of 2025-12-31 |
| Utilities Operating Expense, Depreciation and Amortization | 3.38B | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Gross | 2.79B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, Payments, Due after Rolling Year Five | 607.00M | as of 2025-12-31 |
| Utilities Operating Expense, Taxes | 1.63B | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Valuation Allowance | 49.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, Undiscounted Excess Amount | 393.00M | as of 2025-12-31 |
| Deferred Tax Liabilities, Gross | 13.74B | as of 2025-12-31 |
| Long-term Debt, Gross | 47.71B | as of 2025-12-31 |
| Delinquent Amount at End of Period on Loans Managed and Securitized or Asset-backed Financing Arrangement | 66.00M | as of 2025-12-31 |
| Derivative Assets (Liabilities), at Fair Value, Net | 307.00M | as of 2025-12-31 |
| Recorded Unconditional Purchase Obligation, to be Paid, Year One | 1.86B | as of 2025-12-31 |
| Assets, Fair Value Disclosure | 5.82B | as of 2025-12-31 |
| Recorded Unconditional Purchase Obligation, to be Paid, after Year Five | 535.00M | as of 2025-12-31 |
| Recorded Unconditional Purchase Obligation | 5.63B | as of 2025-12-31 |
| Deferred Tax Liabilities, Investments | 306.00M | as of 2025-12-31 |
| Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) | -14.00M | as of 2025-12-31 |
| Deferred Tax Liabilities, Net | 10.95B | as of 2025-12-31 |
| Defined Benefit Plan, Accumulated Benefit Obligation | 3.60B | as of 2025-12-31 |
| Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation | 45.00M | as of 2025-12-31 |
| Hedged Liability, Fair Value Hedge | 484.00M | as of 2025-12-31 |
| Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets | 0 | as of 2025-12-31 |
| Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation | 45.00M | as of 2025-12-31 |
| Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation | 3.84B | as of 2025-12-31 |
| Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation | 84.00M | as of 2025-12-31 |
| Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets | 3.76B | as of 2025-12-31 |
| Transfers Accounted for as Secured Borrowings, Assets, Carrying Amount | 1.27B | as of 2025-12-31 |
| Transfers Accounted for as Secured Borrowings, Associated Liabilities, Carrying Amount | 900.00M | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year One | 3.19B | as of 2025-12-31 |
| Defined Contribution Plan, Cost | 84.00M | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year Two | 2.45B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Three | 3.47B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Four | 2.89B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Five | 1.81B | as of 2025-12-31 |
| Long-Term Debt, Maturity, after Year Five | 33.90B | as of 2025-12-31 |
| Multiemployer Plan, Employer Contribution, Cost | 471.00K | 2025-01-01 → 2025-12-31 |
| Multiemployer Plans, Withdrawal Obligation | 12.00M | as of 2025-12-31 |
| Income Taxes Receivable, Current | 85.00M | as of 2025-12-31 |
| Other Receivables | 60.00M | as of 2025-12-31 |
| Allowance for Funds Used During Construction, Capitalized Interest | 154.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs | 259.00M | as of 2025-12-31 |
| Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings | 157.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss) | 16.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases, Sales, Issues, Settlements | 286.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3 | 1.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3 | 2.00M | 2025-01-01 → 2025-12-31 |
| Fair Value, Net Derivative Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss) | 19.00M | 2025-01-01 → 2025-12-31 |
| Derivative Liability, Fair Value, Gross Liability | 970.00M | as of 2025-12-31 |
| Derivative Asset, Fair Value, Gross Asset | 1.36B | as of 2025-12-31 |