Fair Value of Financial Instruments (Schedule of Summarized Financial Information of Equity Method Investments) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Summarized Financial Information of Equity Method Investments [Line Items]
Revenue	$ 39.4	$ 37.3
Net income	$ 23.0	$ 19.2

The amount of net income (loss) reported by an equity method investment of the entity.

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