Net Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Net Earnings Per Share - Basic [Abstract]
Net earnings available to common shareholders	$ 68.2	$ 41.0	$ 92.1	$ 81.2
Weighted-average common shares outstanding - basic (in shares)	77.4	80.1	77.3	80.1
Net earnings per share - basic (in dollars per share)	$ 0.88	$ 0.51	$ 1.19	$ 1.01
Net Earnings Per Share - Diluted [Abstract]
Effect of dilutive securities - stock options (in shares)	0.6	0.2	0.6	0.3
Effect of other share-based awards (in shares)	0.6	0.1	0.7	0.4
Weighted-average common shares outstanding - diluted (in shares)	78.6	80.4	78.6	80.8
Net earnings per share - diluted (in dollars per share)	$ 0.87	$ 0.51	$ 1.17	$ 1.01
Share-based awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from the calculation of Net Earnings Per Share (in shares)	2.1	4.2	2.3	4.2