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Commitments And Contingencies (Schedule Of Environmental Liabilities) (Details) - Natural Gas Processing Plant [Member] $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($)
Current and non-current environmental liabilities | $ 18
IPL [Member] |
Current and non-current environmental liabilities | 8
WPL [Member] |
Current and non-current environmental liabilities | 10
Minimum [Member] |
Range of estimated future costs | 9
Minimum [Member] | IPL [Member] |
Range of estimated future costs | 5
Minimum [Member] | WPL [Member] |
Range of estimated future costs | 4
Maximum [Member] |
Range of estimated future costs | 36
Maximum [Member] | IPL [Member] |
Range of estimated future costs | 11
Maximum [Member] | WPL [Member] |
Range of estimated future costs | $ 25

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