Earnings Per Share (Reconciliation of Net Earnings to Net Earnings Attributable to Common Shares Used in Basic and Diluted Calculation) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Earnings from continuing operations	$ 41.5	$ 16.6	$ 72.3	$ 9.5
Earnings allocated to participating non-vested share awards	(0.1)	(0.1)	(0.2)
Earnings from continuing operations attributable to common shares	$ 41.4	$ 16.5	$ 72.1	$ 9.5