Equity Investment (Summary of Investment in Joint Venture, Income Statement Data) (Details) - WAVE [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Schedule of Equity Method Investments [Line Items]
Net sales	$ 96.9	$ 87.7
Gross profit	52.6	47.8
Net earnings	$ 40.2	$ 35.6

The amount of gross profit (loss) reported by an equity method investment of the entity.

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

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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