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v3.6.0.2

Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Deferred tax liabilities, property | $ 2,919.0 | $ 2,762.9
Deferred tax liabilities, other | 95.3 | 157.3
Total deferred tax liabilities | 3,167.4 | 3,058.3
Deferred tax assets, federal credit carryforwards | 268.4 | 236.4
Deferred tax assets, net operating losses carryforwards - federal | 173.3 | 250.9
Deferred tax assets, net operating losses carryforwards - state | 32.9 | 38.3
Deferred tax assets, other | 87.9 | 85.4
Total deferred tax assets | 597.2 | 677.1
Total deferred tax liabilities, net | 2,570.2 | 2,381.2
IPL [Member] |  |
Deferred tax liabilities, property | 1,677.0 | 1,587.8
Deferred tax liabilities, other | 71.4 | 87.8
Total deferred tax liabilities | 1,748.4 | 1,675.6
Deferred tax assets, federal credit carryforwards | 95.9 | 81.7
Deferred tax assets, net operating losses carryforwards - federal | 69.6 | 113.1
Deferred tax assets, net operating losses carryforwards - state | 0.6 | 1.1
Deferred tax assets, other | 35.8 | 35.6
Total deferred tax assets | 236.6 | 297.6
Total deferred tax liabilities, net | 1,511.8 | 1,378.0
WPL [Member] |  |
Deferred tax liabilities, property | 1,124.5 | 1,027.0
Deferred tax liabilities, other | 59.1 | 67.9
Total deferred tax liabilities | 1,183.6 | 1,233.8
Deferred tax assets, federal credit carryforwards | 112.9 | 95.5
Deferred tax assets, net operating losses carryforwards - federal | 75.4 | 105.1
Deferred tax assets, net operating losses carryforwards - state | 0.1 | 3.6
Deferred tax assets, other | 23.6 | 24.2
Total deferred tax assets | 212.0 | 228.4
Total deferred tax liabilities, net | 971.6 | 1,005.4
ATC [Member] |  |
Deferred tax liabilities, investment in ATC | 153.1 | 138.1
ATC [Member] | WPL [Member] |  |
Deferred tax liabilities, investment in ATC | 0.0 | 138.9
IPL's tax benefit riders [Member] |  |
Deferred tax assets, regulatory liability - IPL's tax benefit riders | 34.7 | 66.1
IPL's tax benefit riders [Member] | IPL [Member] |  |
Deferred tax assets, regulatory liability - IPL's tax benefit riders | $ 34.7 | $ 66.1

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