Equity Investments (Summary of Investment in Joint Venture, Balance Sheet Data) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Current assets	$ 321.9	$ 311.8
Current liabilities	209.6	172.3
Other non-current liabilities	980.7	1,095.3
WAVE [Member] | Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member]
Schedule of Equity Method Investments [Line Items]
Current assets	119.7	66.8
Non-current assets	42.1	40.8
Current liabilities	37.1	73.0
Other non-current liabilities	$ 297.4	$ 234.7