Earnings Per Share (Reconciliation of Earnings to Earnings Attributable to Common Shares Used in Basic and Diluted Calculation) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Earnings from continuing operations	$ 36.4	$ 41.2
Earnings allocated to participating non-vested share awards	(0.1)	(0.1)
Earnings from continuing operations attributable to common shares	$ 36.3	$ 41.1

Amount after tax of income (loss) from continuing operations attributable to the parent.

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