Equity Investments (Summary of Investment in Joint Venture, Income Statement Data) (Details) - WAVE [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Net sales	$ 393.2	$ 375.0	$ 344.5
Gross profit	219.6	205.8	192.7
Net earnings	$ 166.0	$ 156.6	$ 144.3