Equity Method Investments (Narrative) (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)
Schedule of Equity Method Investments [Line Items]
Equity method investments summarized financial data basis	100.00%
Loss from equity method investments	$ 17.9	$ 17.3
Clean energy investments
Schedule of Equity Method Investments [Line Items]
Number of equity method investments	3

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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