Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2017

Earnings Per Share [Abstract]

Computation of basic and diluted net income per common share

The following table shows the computation of our basic and diluted net income per common share (in millions, except per share amounts):

	Three Months Ended September 30				Nine Months Ended September 30
	2017		2016		2017		2016
Numerator:
Net income	$	49.0	$	95.7	$	159.9	$	226.2
Denominator:
Weighted average shares outstanding - basic	38.6		40.1		39.0		40.7
Effect of dilutive securities:
Equity compensation plans	0.6		0.5		0.6		0.5
Weighted average shares outstanding - diluted	39.2		40.6		39.6		41.2
Basic earnings per share	$	1.27	$	2.39	$	4.10	$	5.55
Diluted earnings per share	$	1.25	$	2.36	$	4.04	$	5.49