| Fiscal period | 2025 | 2024 | 2023 | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 |
| Period End Date | 12/31/2025 | 12/31/2024 | 12/31/2023 | 12/31/2022 | 12/31/2021 | 12/31/2020 | 12/31/2019 | 12/31/2018 | 12/31/2017 | 12/31/2016 |
| Operating Revenues | 5,140.00 | 4,684.00 | 4,234.00 | 3,792.00 | 3,930.00 | 3,777.00 | 3,610.00 | 3,440.00 | 3,357.00 | 3,302.00 |
| Total Revenues | 5,140.00 | 4,684.00 | 4,234.00 | 3,792.00 | 3,930.00 | 3,777.00 | 3,610.00 | 3,440.00 | 3,357.00 | 3,302.00 |
| Operation and maintenance | 2,019.00 | 1,858.00 | 1,720.00 | 1,589.00 | 1,777.00 | 1,622.00 | 1,544.00 | 1,479.00 | 1,378.00 | 1,504.00 |
| Depreciation and amortization | 894.00 | 788.00 | 704.00 | 649.00 | 636.00 | 604.00 | 582.00 | 545.00 | 492.00 | 470.00 |
| Amortization of debt expense | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| General taxes | 348.00 | 320.00 | 307.00 | 281.00 | 321.00 | 303.00 | 280.00 | 277.00 | 259.00 | 258.00 |
| (Gain) loss on sales of assets | -- | -- | -- | -- | -- | -- | (34.00) | 20.00 | 16.00 | 10.00 |
| Other | -- | -- | 1.00 | -- | -- | -- | -- | -- | -- | -- |
| Impairment charge | -- | -- | -- | -- | -- | -- | -- | (57.00) | -- | -- |
| Total Operating Expenses | 3,261.00 | 2,966.00 | 2,730.00 | 2,519.00 | 2,734.00 | 2,529.00 | 2,440.00 | 2,338.00 | 2,113.00 | 2,222.00 |
| Operating income (loss) | 1,879.00 | 1,718.00 | 1,504.00 | 1,273.00 | 1,196.00 | 1,248.00 | 1,170.00 | 1,102.00 | 1,244.00 | 1,080.00 |
| Interest, net | 615.00 | 523.00 | 460.00 | 433.00 | 403.00 | 395.00 | 382.00 | 350.00 | 342.00 | 325.00 |
| Amortization of debt expense | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Preferred dividends of subsidiaries | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Interest income | 90.00 | 94.00 | 73.00 | 52.00 | 4.00 | -- | -- | -- | -- | -- |
| Allowance for other funds used during construction | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Allowance for borrowed funds used during construction | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Other, net | 52.00 | 42.00 | 47.00 | 20.00 | 18.00 | 22.00 | 33.00 | 19.00 | 17.00 | 15.00 |
| Gain (loss) on extinguishment of debt | -- | -- | -- | -- | -- | -- | (4.00) | (4.00) | (7.00) | -- |
| Non-operating benefit costs, net | 16.00 | 28.00 | 32.00 | 77.00 | 78.00 | 49.00 | 16.00 | 20.00 | -- | -- |
| Gain or (loss) on sale of businesses | -- | -- | -- | 19.00 | 747.00 | -- | -- | -- | -- | -- |
| Income (loss) from continuing operations before income taxes | 1,422.00 | 1,359.00 | 1,196.00 | 1,008.00 | 1,640.00 | 924.00 | 833.00 | 787.00 | 912.00 | 770.00 |
| Provision for income taxes | 311.00 | 308.00 | 252.00 | 188.00 | 377.00 | 215.00 | 212.00 | 222.00 | 486.00 | 302.00 |
| Amortization of deferred investment tax credits | (1.00) | (1.00) | (1.00) | (1.00) | (1.00) | (1.00) | (1.00) | (1.00) | (1.00) | (1.00) |
| State income taxes : Current | 25.00 | 16.00 | 16.00 | 26.00 | 72.00 | 8.00 | 4.00 | 26.00 | 25.00 | 20.00 |
| State income taxes : Deferred - Current | 36.00 | 53.00 | 44.00 | 24.00 | 10.00 | 49.00 | 54.00 | 33.00 | 50.00 | 24.00 |
| State income taxes : Deferred - Non-current | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Federal income taxes : Current | 151.00 | 136.00 | 28.00 | 82.00 | 75.00 | -- | -- | 1.00 | (1.00) | 1.00 |
| Federal income taxes : Deferred - Current | 100.00 | 104.00 | 165.00 | 57.00 | 221.00 | 159.00 | 155.00 | 163.00 | 413.00 | 258.00 |
| Federal income taxes : Deferred - Non-current | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Income (Loss) from Continuing Operations | -- | -- | -- | -- | -- | -- | -- | -- | -- | 468.00 |
| Income (Loss) from Discontinued Operations, Net of Tax | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| Consolidated Net income | 1,111.00 | 1,051.00 | 944.00 | 820.00 | 1,263.00 | 709.00 | 621.00 | 565.00 | -- | -- |
| Net loss attributable to noncontrolling interest | -- | -- | -- | -- | -- | -- | -- | (2.00) | -- | -- |
| Net Income (Loss) available to limited partners shareholders | 1,111.00 | 1,051.00 | 944.00 | 820.00 | 1,263.00 | 709.00 | 621.00 | 567.00 | 426.00 | 468.00 |
| Income (loss) from continuing operations | -- | -- | -- | -- | -- | -- | -- | -- | -- | 2.63 |
| Income (loss) from discontinued operations, net of tax | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| NET EARNINGS PER SHARE (BASIC) | 5.69 | 5.39 | 4.90 | 4.51 | 6.96 | 3.91 | 3.44 | 3.16 | 2.39 | 2.63 |
| Income (loss) from continuing operations | -- | -- | -- | -- | -- | -- | -- | -- | -- | 2.62 |
| Income (loss) from discontinued operations, net of tax | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- |
| NET EARNINGS PER SHARE (DILUTED) | 5.69 | 5.39 | 4.90 | 4.51 | 6.95 | 3.91 | 3.43 | 3.15 | 2.38 | 2.62 |
| Weighted Average Shares Outstanding (Basic) | 195.00 | 195.00 | 193.00 | 182.00 | 182.00 | 181.00 | 181.00 | 180.00 | 178.00 | 178.00 |
| Weighted Average Shares Outstanding (Diluted) | 195.00 | 195.00 | 193.00 | 182.00 | 182.00 | 182.00 | 181.00 | 180.00 | 179.00 | 179.00 |