Nature of Operations (Reconciliation Of Total Consolidated Operating Income To Earnings Before Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Total consolidated operating income	$ 317.4	$ 249.4	$ 243.8
Interest expense	38.4	39.2	35.4
Other non-operating (income), net	(20.4)	(32.5)	(13.7)
Earnings from continuing operations before income taxes	$ 299.4	$ 242.7	$ 222.1

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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