Variable Interest Entities (Schedule of Net Income Attributable to Noncontrolling Interest) (Details) - USD ($) $ in Millions	12 Months Ended
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

Amount of Net Income (Loss) attributable to noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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