Earnings per Share

12 Months Ended

Dec. 31, 2013

Earnings Per Share [Abstract]

Earnings per Share

7. Earnings per Share

The following table sets forth the computation of basic and diluted net earnings per share (in millions, except per share data):

	Year Ended December 31,
	2013		2012		2011
Net earnings	$	268.6	$	195.0	$	144.1
Weighted average number of common shares outstanding		128.9		121.0		111.7
Dilutive effect of stock options using the treasury stock method		1.6		1.5		0.8
Weighted average number of common and common equivalent shares outstanding		130.5		122.5		112.5
Basic net earnings per share	$	2.08	$	1.61	$	1.29
Diluted net earnings per share:	$	2.06	$	1.59	$	1.28

Options to purchase 1.3 million, 1.1 million and 3.8 million shares of our common stock were outstanding at December 31, 2013, 2012 and 2011, respectively, but were not included in the computation of the dilutive effect of stock options for the year then ended. These stock options were excluded from the computation because the options’ exercise prices were greater than the average market price of our common shares during the respective period and, therefore, would be anti-dilutive to earnings per share under the treasury stock method.