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Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Deferred tax liabilities, property | $ 2,453 | $ 2,442
Deferred tax liabilities, other | 213 | 155
Total deferred tax liabilities | 2,793 | 2,722
Deferred tax assets, federal credit carryforwards | 649 | 672
Deferred tax assets, net operating losses carryforwards - state | 26 | 32
Deferred tax assets, other | 79 | 75
Subtotal deferred tax assets | 754 | 779
Deferred tax assets, valuation allowances | (3) | 0
Total deferred tax assets | 751 | 779
Total deferred tax liabilities, net | 2,042 | 1,943
IPL [Member] |  |
Deferred tax liabilities, property | 1,415 | 1,440
Deferred tax liabilities, other | 157 | 86
Total deferred tax liabilities | 1,572 | 1,526
Deferred tax assets, federal credit carryforwards | 449 | 450
Deferred tax assets, net operating losses carryforwards - state | 1 | 0
Deferred tax assets, other | 32 | 29
Subtotal deferred tax assets | 482 | 479
Deferred tax assets, valuation allowances | (1) | 0
Total deferred tax assets | 481 | 479
Total deferred tax liabilities, net | 1,091 | 1,047
WPL [Member] |  |
Deferred tax liabilities, property | 972 | 938
Deferred tax liabilities, other | 64 | 80
Total deferred tax liabilities | 1,036 | 1,018
Deferred tax assets, federal credit carryforwards | 191 | 209
Deferred tax assets, net operating losses carryforwards - state | 0 | 0
Deferred tax assets, other | 19 | 20
Subtotal deferred tax assets | 210 | 229
Deferred tax assets, valuation allowances | (1) | 0
Total deferred tax assets | 209 | 229
Total deferred tax liabilities, net | 827 | 789
ATC Holdings [Member] |  |
Deferred tax liabilities, ATC Holdings | 127 | 125
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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