| **Acquisitions (Schedule Of Purchase Price Allocation) (Details) - Peoples Gas Acquisition [Member] $ in Thousands** | Mar. 16, 2020 USD ($) |
|----------------------------------------------------------------------------------------------------------------------|-----------------------|
| **Business Acquisition [Line Items]**                                                                                |                  |
| Base purchase price                                                                                                  | $ 4,275,000           |
| Estimated change in working capital                                                                                  | 43,935                |
| Certain estimated capital expenditures                                                                               | 247,500               |
| Assumption of indebtedness                                                                                           | (1,101,091)           |
| Cash consideration                                                                                                   | $ 3,465,344           |

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| - Definition
Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.
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| - Definition
The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.
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