Net Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Net Earnings Per Share - Basic [Abstract]
Net earnings available to common shareholders	$ 70.1	$ 23.9
Weighted-average common shares outstanding (in shares)	79.8	77.1
Net earnings per share - basic (in dollars per share)	$ 0.88	$ 0.31
Net Earnings Per Share - Diluted [Abstract]
Net earnings available to common shareholders	$ 70.1	$ 23.9
Weighted-average common shares outstanding (in shares)	79.8	77.1
Effect of dilutive securities - stock options (in shares)	0.7	0.6
Effect of other share-based awards (in shares)	0.7	0.5
Weighted-average common shares outstanding - diluted (in shares)	81.2	78.2
Net earnings per share - diluted (in dollars per share)	$ 0.86	$ 0.31
Share-based awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share - Diluted [Line Items]
Antidilutive securities excluded from the calculation of Net Earnings Per Share - Diluted (in shares)	0.1	3.4