Net Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2020

Earnings Per Share [Abstract]

Calculations of Net Earnings Per Share - Basic and Diluted

The calculation of net earnings per share - basic and net earnings per share - diluted were as follows:

Year Ended December 31	2020		2019		2018
Net earnings available to common shareholders:	$	23.8	$	465.7	$	556.7
Weighted-average common shares outstanding (in millions):
Weighted-average common shares outstanding - basic		58.0		59.9		64.6
Effect of dilutive securities - stock options		—		—		0.1
Effect of other share-based awards		0.3		0.4		0.4
Weighted-average common shares outstanding - diluted		58.3		60.3		65.1
Net earnings per share - basic	$	0.41	$	7.78	$	8.62
Net earnings per share - diluted	$	0.41	$	7.72	$	8.56