Equity Investment (Summary of Investment in Joint Venture, Income Statement Data) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Schedule of Equity Method Investments [Line Items]
Net sales	$ 292.2	$ 246.3	$ 824.1	$ 698.2
Gross profit	110.7	91.2	303.1	250.3
Net earnings	50.8	54.0	141.3	(121.9)
WAVE [Member] | Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member]
Schedule of Equity Method Investments [Line Items]
Net sales	114.2	86.3	321.5	257.0
Gross profit	64.5	49.4	188.0	145.7
Net earnings	$ 49.1	$ 33.4	$ 143.2	$ 103.3