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Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Deferred tax liabilities, property | $ 2,596 | $ 2,453
Deferred tax liabilities, other | 178 | 213
Total deferred tax liabilities | 2,909 | 2,793
Deferred tax assets, federal credit carryforwards | 605 | 649
Deferred tax assets, net operating losses carryforwards - state | 20 | 26
Deferred tax assets, other | 98 | 79
Subtotal deferred tax assets | 723 | 754
Deferred tax assets, valuation allowances | (2) | (3)
Total deferred tax assets | 721 | 751
Total deferred tax liabilities, net | 2,188 | 2,042
IPL [Member] |  |
Deferred tax liabilities, property | 1,521 | 1,415
Deferred tax liabilities, other | 120 | 157
Total deferred tax liabilities | 1,641 | 1,572
Deferred tax assets, federal credit carryforwards | 426 | 449
Deferred tax assets, net operating losses carryforwards - state | 1 | 1
Deferred tax assets, other | 37 | 32
Subtotal deferred tax assets | 464 | 482
Deferred tax assets, valuation allowances | (2) | (1)
Total deferred tax assets | 462 | 481
Total deferred tax liabilities, net | 1,179 | 1,091
WPL [Member] |  |
Deferred tax liabilities, property | 999 | 972
Deferred tax liabilities, other | 66 | 64
Total deferred tax liabilities | 1,065 | 1,036
Deferred tax assets, federal credit carryforwards | 166 | 191
Deferred tax assets, net operating losses carryforwards - state | 0 | 0
Deferred tax assets, other | 34 | 19
Subtotal deferred tax assets | 200 | 210
Deferred tax assets, valuation allowances | 0 | (1)
Total deferred tax assets | 200 | 209
Total deferred tax liabilities, net | 865 | 827
ATC Holdings [Member] |  |
Deferred tax liabilities, ATC Holdings | 135 | 127
ATC Holdings [Member] | IPL [Member] |  |
Deferred tax liabilities, ATC Holdings | 0 | 0
ATC Holdings [Member] | WPL [Member] |  |
Deferred tax liabilities, ATC Holdings | $ 0 | $ 0

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