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v3.10.0.1

Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Deferred tax liabilities, property | $ 1,975.5 | $ 1,852.7
Deferred tax liabilities, other | 80.5 | 75.9
Total deferred tax liabilities | 2,158.4 | 2,015.0
Deferred tax assets, federal credit carryforwards | 299.1 | 260.7
Deferred tax assets, net operating losses carryforwards - federal | 158.6 | 174.4
Deferred tax assets, net operating losses carryforwards - state | 47.0 | 41.3
Deferred tax assets, other | 59.8 | 69.2
Subtotal deferred tax assets | 564.5 | 545.6
Deferred tax assets, valuation allowances | (9.2) | (9.0)
Total deferred tax assets | 555.3 | 536.6
Total deferred tax liabilities, net | 1,603.1 | 1,478.4
IPL [Member] |  |
Deferred tax liabilities, property | 1,158.4 | 1,102.6
Deferred tax liabilities, other | 69.4 | 63.4
Total deferred tax liabilities | 1,227.8 | 1,166.0
Deferred tax assets, federal credit carryforwards | 133.2 | 113.1
Deferred tax assets, net operating losses carryforwards - federal | 114.1 | 107.4
Deferred tax assets, net operating losses carryforwards - state | 0.9 | 0.9
Deferred tax assets, other | 22.8 | 34.5
Subtotal deferred tax assets | 271.0 | 255.9
Deferred tax assets, valuation allowances | (0.5) | (0.6)
Total deferred tax assets | 270.5 | 255.3
Total deferred tax liabilities, net | 957.3 | 910.7
WPL [Member] |  |
Deferred tax liabilities, property | 735.2 | 674.2
Deferred tax liabilities, other | 34.4 | 36.5
Total deferred tax liabilities | 769.6 | 710.7
Deferred tax assets, federal credit carryforwards | 147.4 | 131.0
Deferred tax assets, net operating losses carryforwards - federal | 26.4 | 43.7
Deferred tax assets, net operating losses carryforwards - state | 0.5 | 0.2
Deferred tax assets, other | 14.1 | 14.7
Subtotal deferred tax assets | 188.4 | 189.6
Deferred tax assets, valuation allowances | (0.8) | (1.3)
Total deferred tax assets | 187.6 | 188.3
Total deferred tax liabilities, net | 582.0 | 522.4
ATC Holdings [Member] |  |
Deferred tax liabilities, ATC Holdings | $ 102.4 | $ 86.4

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