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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, 2022 USD ($)
Current and non-current environmental liabilities | $ 11
IPL [Member] |
Current and non-current environmental liabilities | 8
Minimum [Member] |
Range of estimated future costs | 9
Minimum [Member] | IPL [Member] |
Range of estimated future costs | 6
Maximum [Member] |
Range of estimated future costs | 25
Maximum [Member] | IPL [Member] |
Range of estimated future costs | $ 19

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