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v3.20.4

Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Deferred tax liabilities, property | $ 2,232 | $ 2,022
Deferred tax liabilities, other | 101 | 84
Total deferred tax liabilities | 2,449 | 2,217
Deferred tax assets, federal credit carryforwards | 454 | 355
Deferred tax assets, net operating losses carryforwards - federal | 77 | 60
Deferred tax assets, net operating losses carryforwards - state | 37 | 37
Deferred tax assets, other | 73 | 61
Subtotal deferred tax assets | 641 | 513
Deferred tax assets, valuation allowances | (6) | (10)
Total deferred tax assets | 635 | 503
Total deferred tax liabilities, net | 1,814 | 1,714
IPL [Member] |  |
Deferred tax liabilities, property | 1,312 | 1,184
Deferred tax liabilities, other | 83 | 76
Total deferred tax liabilities | 1,395 | 1,260
Deferred tax assets, federal credit carryforwards | 258 | 175
Deferred tax assets, net operating losses carryforwards - federal | 71 | 56
Deferred tax assets, net operating losses carryforwards - state | 1 | 1
Deferred tax assets, other | 30 | 20
Subtotal deferred tax assets | 360 | 252
Deferred tax assets, valuation allowances | 0 | 0
Total deferred tax assets | 360 | 252
Total deferred tax liabilities, net | 1,035 | 1,008
WPL [Member] |  |
Deferred tax liabilities, property | 854 | 770
Deferred tax liabilities, other | 41 | 32
Total deferred tax liabilities | 895 | 802
Deferred tax assets, federal credit carryforwards | 175 | 160
Deferred tax assets, net operating losses carryforwards - federal | 1 | 1
Deferred tax assets, net operating losses carryforwards - state | 0 | 0
Deferred tax assets, other | 18 | 16
Subtotal deferred tax assets | 194 | 177
Deferred tax assets, valuation allowances | (1) | (1)
Total deferred tax assets | 193 | 176
Total deferred tax liabilities, net | 702 | 626
ATC Holdings [Member] |  |
Deferred tax liabilities, ATC Holdings | $ 116 | $ 111

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