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Variable Interest Entities (Schedule of Net Income Attributable to Noncontrolling Interest) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Income Attributable to noncontrolling [Line Items] |  |  |
Net income attributable to noncontrolling interest | $ 3.9 | $ 3.4 | $ 0.0
Rosewater |  |  |
Income Attributable to noncontrolling [Line Items] |  |  |
Net income attributable to noncontrolling interest | (4.2) | 3.4 | 0.0
Indiana Crossroads Wind |  |  |
Income Attributable to noncontrolling [Line Items] |  |  |
Net income attributable to noncontrolling interest | $ 8.1 | $ 0.0 | $ 0.0

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