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v3.3.0.814

Income Taxes (Narrative) (Details) $ in Millions | 9 Months Ended
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Sep. 30, 2015 USD ($)
Income Taxes [Line Items] |
Increase (decrease) non-current deferred tax liabilities | $ 141.0
IPL [Member] |
Income Taxes [Line Items] |
Increase (decrease) non-current deferred tax liabilities | 78.5
WPL [Member] |
Income Taxes [Line Items] |
Increase (decrease) non-current deferred tax liabilities | $ 60.1

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- Details
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