| Current Federal Tax Expense (Benefit) | 170.00M | 2025-01-01 → 2025-12-31 |
| Current State and Local Tax Expense (Benefit) | -7.00M | 2025-01-01 → 2025-12-31 |
| Current Federal, State and Local, Tax Expense (Benefit) | 163.00M | 2025-01-01 → 2025-12-31 |
| Deferred Federal Income Tax Expense (Benefit) | -48.00M | 2025-01-01 → 2025-12-31 |
| Deferred State and Local Income Tax Expense (Benefit) | 154.00M | 2025-01-01 → 2025-12-31 |
| Deferred Federal, State and Local, Tax Expense (Benefit) | 106.00M | 2025-01-01 → 2025-12-31 |
| Asset Retirement Obligation, Liabilities Settled | 12.00M | 2025-01-01 → 2025-12-31 |
| Asset Retirement Obligation, Revision of Estimate | -170.00M | 2025-01-01 → 2025-12-31 |
| Other Tax Expense (Benefit) | -9.00M | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense | 24.00M | 2025-01-01 → 2025-12-31 |
| Share-based Payment Arrangement, Expense | 43.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount | 499.00M | 2025-01-01 → 2025-12-31 |
| Share-based Payment Arrangement, Expense, Tax Benefit | 12.00M | 2025-01-01 → 2025-12-31 |
| Long-term Debt, Fair Value | 21.36B | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount | 20.00M | 2025-01-01 → 2025-12-31 |
| Line of Credit Facility, Fair Value of Amount Outstanding | 1.15B | as of 2025-12-31 |
| Line of Credit Facility, Maximum Borrowing Capacity | 3.83B | as of 2025-12-31 |
| Line of Credit Facility, Remaining Borrowing Capacity | 2.67B | as of 2025-12-31 |
| Deferred Costs and Other Assets | 10.92B | as of 2025-12-31 |
| SegmentExpenditureAdditionToLongLivedAssets | 3.27B | 2025-01-01 → 2025-12-31 |
| Dividends, Common Stock, Cash | 1.26B | 2025-01-01 → 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Plant in Service | 53.92B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Accumulated Depreciation | 11.86B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Net | 42.06B | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Other Adjustments, Amount | 1.00M | 2025-01-01 → 2025-12-31 |
| Derivative, Fair Value, Net | -69.00M | as of 2025-12-31 |
| Deferred Income Taxes and Other Tax Liabilities, Noncurrent | 7.93B | as of 2025-12-31 |
| Defined Benefit Plan, Plan Assets, Amount | 4.74B | as of 2025-12-31 |
| Derivative, Fair Value, Amount Offset Against Collateral, Net | 99.00M | as of 2025-12-31 |
| Operating Lease, Cost | 63.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Other | 43.00M | as of 2025-12-31 |
| Short-term Lease, Cost | 20.00M | 2025-01-01 → 2025-12-31 |
| Variable Lease, Cost | 14.00M | 2025-01-01 → 2025-12-31 |
| Lease, Cost | 97.00M | 2025-01-01 → 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year One | 34.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Two | 31.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Three | 27.00M | as of 2025-12-31 |
| Deferred Tax Assets, Regulatory Assets and Liabilities | 365.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Four | 26.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Five | 22.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, after Year Five | 39.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid | 179.00M | as of 2025-12-31 |
| Deferred Tax Assets, Other | 144.00M | as of 2025-12-31 |
| Utilities Operating Expense, Maintenance and Operations | 3.77B | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Gross | 670.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, Undiscounted Excess Amount | 23.00M | as of 2025-12-31 |
| Deferred Tax Liabilities, Gross | 8.55B | as of 2025-12-31 |
| Employee Stock Ownership Plan (ESOP), Compensation Expense | 2.00M | 2025-01-01 → 2025-12-31 |
| Long-term Debt, Gross | 22.71B | as of 2025-12-31 |
| Deferred Tax Liabilities, Property, Plant and Equipment | 5.38B | as of 2025-12-31 |
| Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax | -7.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Liabilities, Leasing Arrangements | 30.00M | as of 2025-12-31 |
| Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax | -11.00M | 2025-01-01 → 2025-12-31 |
| Operating Lease, Lease Income, Lease Payments | 14.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Liabilities, Other | 214.00M | as of 2025-12-31 |
| Deferred Tax Liabilities, Net | 7.88B | as of 2025-12-31 |
| Defined Benefit Plan, Accumulated Benefit Obligation | 4.50B | as of 2025-12-31 |
| Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months | 4.00M | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year One | 875.00M | as of 2025-12-31 |
| Defined Contribution Plan, Cost | 51.00M | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year Two | 1.13B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Three | 1.30B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Four | 1.13B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Five | 2.20B | as of 2025-12-31 |
| Long-Term Debt, Maturity, after Year Five | 16.09B | as of 2025-12-31 |
| Capitalization, Long-term Debt and Equity | 38.65B | as of 2025-12-31 |
| Operating Loss Carryforwards | 11.00M | as of 2025-12-31 |
| Operating Lease, Variable Lease Income | 0 | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits | 196.00M | as of 2025-12-31 |
| Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions | 35.00M | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions | 47.00M | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions | 0 | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Decrease Resulting from Current Period Tax Positions | 0 | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations | 1.00M | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits that Would Impact Effective Tax Rate | 164.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year One | 14.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year Two | 14.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year Three | 14.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year Four | 14.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year Five | 14.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, after Year Five | 94.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payments to be Received | 164.00M | as of 2025-12-31 |
| Income Taxes Receivable, Current | 406.00M | as of 2025-12-31 |
| Pension and Other Postretirement Benefits Cost (Reversal of Cost) | 76.00M | 2025-01-01 → 2025-12-31 |
| Collateral Already Posted, Aggregate Fair Value | 222.00M | as of 2025-12-31 |