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Segments Of Business (Schedule Of Operating Income Derived From Revenues And Expenses By Segment) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Segment Reporting Information [Line Items] |  |  |
Operating Revenues | $ 4,899.6 | $ 4,681.7 | $ 5,208.9
Operating Income | 1,006.9 | 550.8 | 890.7
Consolidated Depreciation and Amortization | 748.4 | 725.9 | 717.4
Consolidated Assets | 24,156.9 | 22,040.5 | 22,659.8
Payments to Acquire Property Plant and Equipment Including Captial Expenditures From Current Liabilities And Equity Method Investments | 1,940.4 | 1,720.8 | 1,867.8
Disposal Group, Not Discontinued Operation, Loss (Gain) on Write-down |  | 412.4 |
Gas Distribution Operations |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenues | 3,171.2 | 3,128.1 | 3,509.7
Intersegment | 3,183.5 | 3,140.2 | 3,522.8
Operating Income | 617.5 | 199.1 | 675.4
Consolidated Depreciation and Amortization | 383.0 | 363.1 | 403.2
Consolidated Assets | 15,153.7 | 13,433.0 | 14,224.5
Payments to Acquire Property Plant and Equipment Including Captial Expenditures From Current Liabilities And Equity Method Investments | 1,406.4 | 1,266.9 | 1,380.3
Electric Operations |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenues | 1,696.3 | 1,535.9 | 1,698.4
Intersegment | 1,697.1 | 1,536.6 | 1,699.2
Operating Income | 387.8 | 348.8 | 406.8
Consolidated Depreciation and Amortization | 329.4 | 321.3 | 277.3
Consolidated Assets | 7,178.9 | 6,443.1 | 6,027.6
Payments to Acquire Property Plant and Equipment Including Captial Expenditures From Current Liabilities And Equity Method Investments | 517.4 | 422.8 | 468.9
Corporate and Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenues | 32.1 | 17.7 | 0.8
Intersegment | 492.4 | 467.5 | 468.9
Operating Income | 1.6 | 2.9 | (191.5)
Consolidated Depreciation and Amortization | 36.0 | 41.5 | 36.9
Consolidated Assets | 1,824.3 | 2,164.4 | 2,407.7
Payments to Acquire Property Plant and Equipment Including Captial Expenditures From Current Liabilities And Equity Method Investments | 16.6 | 31.1 | 18.6
Unaffiliated | Gas Distribution Operations |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenues | 3,171.2 | 3,128.1 | 3,509.7
Unaffiliated | Electric Operations |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenues | 1,696.3 | 1,535.9 | 1,698.4
Unaffiliated | Corporate and Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenues | 32.1 | 17.7 | 0.8
Intersegment | Gas Distribution Operations |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment | 12.3 | 12.1 | 13.1
Intersegment | Electric Operations |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment | 0.8 | 0.7 | 0.8
Intersegment | Corporate and Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment | 460.3 | 449.8 | 468.1
Eliminations |  |  |
Segment Reporting Information [Line Items] |  |  |
Intersegment | $ (473.4) | $ (462.6) | $ (482.0)

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