Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2015

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 for the years ending December 31 (in millions, except per share amounts):

	2015		2014		2013
Numerator:
Net income	$	205.3	$	205.0	$	169.3
Denominator:
Weighted average shares outstanding - basic	43.1		45.0		46.4
Effect of dilutive securities:
Equity compensation plans	0.7		0.8		0.7
Weighted average shares outstanding - diluted	43.8		45.8		47.1
Basic earnings per share	$	4.76	$	4.55	$	3.64
Diluted earnings per share	$	4.69	$	4.48	$	3.59