| Current Federal Tax Expense (Benefit) | 139.00M | 2025-01-01 → 2025-12-31 |
| Current State and Local Tax Expense (Benefit) | 94.00M | 2025-01-01 → 2025-12-31 |
| Cash and Cash Equivalents, Fair Value Disclosure | 1.10B | as of 2025-12-31 |
| Deferred Federal Income Tax Expense (Benefit) | 399.00M | 2025-01-01 → 2025-12-31 |
| Deferred State and Local Income Tax Expense (Benefit) | 196.00M | 2025-01-01 → 2025-12-31 |
| Asset Retirement Obligation, Liabilities Incurred | 6.00M | 2025-01-01 → 2025-12-31 |
| Asset Retirement Obligation, Liabilities Settled | 634.00M | 2025-01-01 → 2025-12-31 |
| Operating Lease, Liability, Current | 197.00M | as of 2025-12-31 |
| Other Inventory, Supplies, Gross | 2.20B | as of 2025-12-31 |
| Asset Retirement Obligation, Revision of Estimate | -98.00M | 2025-01-01 → 2025-12-31 |
| Accrued Salaries, Current | 1.42B | as of 2025-12-31 |
| Federal Income Tax Expense (Benefit), Continuing Operations | 538.00M | 2025-01-01 → 2025-12-31 |
| State and Local Income Tax Expense (Benefit), Continuing Operations | 290.00M | 2025-01-01 → 2025-12-31 |
| Other Assets, Fair Value Disclosure | 11.00M | as of 2025-12-31 |
| Energy Related Inventory, Natural Gas in Storage | 396.00M | as of 2025-12-31 |
| Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity | 340.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount | 1.05B | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount | 254.00M | 2025-01-01 → 2025-12-31 |
| Energy Related Inventory, Other Fossil Fuel | 735.00M | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Credit, Other, Amount | 2.00M | 2025-01-01 → 2025-12-31 |
| Contract with Customer, Liability, Revenue Recognized | 102.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount | 19.00M | 2025-01-01 → 2025-12-31 |
| Line of Credit Facility, Maximum Borrowing Capacity | 8.92B | as of 2025-12-31 |
| Line of Credit Facility, Remaining Borrowing Capacity | 8.91B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Generation or Processing | 63.53B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Transmission | 17.81B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Distribution | 31.72B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Fuel | 897.00M | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Construction Work in Progress | 10.53B | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Tax Contingency, Amount | -26.00M | 2025-01-01 → 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment | 307.00M | as of 2025-12-31 |
| SegmentReportingOtherItemAmount | 15.76B | 2025-01-01 → 2025-12-31 |
| Dividends, Common Stock, Cash | 3.24B | 2025-01-01 → 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Plant in Service | 146.11B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Accumulated Depreciation | 43.48B | as of 2025-12-31 |
| Public Utilities, Property, Plant and Equipment, Net | 114.37B | as of 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Noncontrolling Interest Income (Loss), Amount | -36.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount | -170.00M | 2025-01-01 → 2025-12-31 |
| Effective Income Tax Rate Reconciliation, Other Adjustments, Amount | -44.00M | 2025-01-01 → 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year One | 27.00M | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Two | 24.00M | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Three | 24.00M | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Four | 23.00M | as of 2025-12-31 |
| Finite-Lived Intangible Asset, Expected Amortization, Year Five | 21.00M | as of 2025-12-31 |
| Derivative Asset, Fair Value, Gross Liability | 21.00M | as of 2025-12-31 |
| Derivative Liability, Fair Value, Gross Asset | 54.00M | as of 2025-12-31 |
| Intangible Assets, Gross (Excluding Goodwill) | 744.00M | as of 2025-12-31 |
| Deferred Credits and Other Liabilities | 34.32B | as of 2025-12-31 |
| Deferred Tax Assets, Operating Loss Carryforwards, State and Local | 250.00M | as of 2025-12-31 |
| Net Regulatory Assets | 6.89B | as of 2025-12-31 |
| Stock Issued During Period, Value, New Issues | 1.84B | 2025-01-01 → 2025-12-31 |
| Operating Lease, Cost | 271.00M | 2025-01-01 → 2025-12-31 |
| Short-term Lease, Cost | 45.00M | 2025-01-01 → 2025-12-31 |
| Variable Lease, Cost | 52.00M | 2025-01-01 → 2025-12-31 |
| Lease, Cost | 392.00M | 2025-01-01 → 2025-12-31 |
| Right-of-Use Asset Obtained in Exchange for Finance Lease Liability | 509.00M | 2025-01-01 → 2025-12-31 |
| Right-of-Use Asset Obtained in Exchange for Operating Lease Liability | 168.00M | 2025-01-01 → 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year One | 33.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year Two | 32.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year Three | 44.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year Four | 65.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, Year Five | 67.00M | as of 2025-12-31 |
| Finance Lease, Liability, to be Paid, after Year Five | 1.13B | as of 2025-12-31 |
| Finance Lease, Liability, Payment, Due | 1.37B | as of 2025-12-31 |
| Finance Lease, Liability, Undiscounted Excess Amount | 603.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year One | 233.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Two | 217.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Three | 202.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Four | 168.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, Year Five | 118.00M | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid, after Year Five | 1.29B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, to be Paid | 2.23B | as of 2025-12-31 |
| Utilities Operating Expense, Maintenance and Operations | 7.07B | 2025-01-01 → 2025-12-31 |
| Deferred Tax Assets, Gross | 7.67B | as of 2025-12-31 |
| Deferred Tax Assets, Valuation Allowance | 445.00M | as of 2025-12-31 |
| Deferred Tax Assets, Net of Valuation Allowance | 7.22B | as of 2025-12-31 |
| Lessee, Operating Lease, Liability, Undiscounted Excess Amount | 748.00M | as of 2025-12-31 |
| Deferred Tax Liabilities, Gross | 19.29B | as of 2025-12-31 |
| Sales-type and Direct Financing Leases, Lease Receivable | 286.00M | as of 2025-12-31 |
| Assets, Fair Value Disclosure | 4.24B | as of 2025-12-31 |
| Other Liabilities, Fair Value Disclosure | 24.00M | as of 2025-12-31 |
| Financial and Nonfinancial Liabilities, Fair Value Disclosure | 359.00M | as of 2025-12-31 |
| Variable Lease, Income | 408.00M | 2025-01-01 → 2025-12-31 |
| Deferred Tax Liabilities, Net | 12.07B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year One | 6.21B | as of 2025-12-31 |
| Defined Contribution Plan, Cost | 148.00M | 2025-01-01 → 2025-12-31 |
| Long-Term Debt, Maturity, Year Two | 3.41B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Three | 5.46B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Four | 1.99B | as of 2025-12-31 |
| Long-Term Debt, Maturity, Year Five | 4.10B | as of 2025-12-31 |
| Operating Loss Carryforwards, Valuation Allowance | 85.00M | as of 2025-12-31 |
| Debt Instrument, Unamortized Discount (Premium), Net | 56.00M | as of 2025-12-31 |
| Unrecognized Tax Benefits | 170.00M | as of 2025-12-31 |
| Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions | 122.00M | 2025-01-01 → 2025-12-31 |
| Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations | 34.00M | 2025-01-01 → 2025-12-31 |
| Extinguishment of Debt, Gain (Loss), Net of Tax | -189.00M | 2025-01-01 → 2025-12-31 |
| Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year One | 39.00M | as of 2025-12-31 |
| Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Two | 38.00M | as of 2025-12-31 |
| Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Three | 37.00M | as of 2025-12-31 |
| Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Four | 36.00M | as of 2025-12-31 |
| Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Five | 34.00M | as of 2025-12-31 |
| Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, after Year Five | 270.00M | as of 2025-12-31 |
| Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received | 454.00M | as of 2025-12-31 |
| Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount | 168.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year One | 119.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year Two | 111.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year Three | 111.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year Four | 116.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, Year Five | 115.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payment to be Received, after Year Five | 554.00M | as of 2025-12-31 |
| Lessor, Operating Lease, Payments to be Received | 1.13B | as of 2025-12-31 |
| Pension and Other Postretirement Benefits Cost (Reversal of Cost) | -579.00M | 2025-01-01 → 2025-12-31 |
| Other Receivables, Net, Current | 655.00M | as of 2025-12-31 |
| Allowance for Funds Used During Construction, Capitalized Interest | 480.00M | 2025-01-01 → 2025-12-31 |
| Collateral Already Posted, Aggregate Fair Value | 33.00M | as of 2025-12-31 |
| Derivative Liability, Fair Value, Gross Liability | 321.00M | as of 2025-12-31 |
| Derivative Asset, Fair Value, Gross Asset | 93.00M | as of 2025-12-31 |
| APIC, Share-based Payment Arrangement, Increase for Cost Recognition | 48.00M | 2025-01-01 → 2025-12-31 |