Net Income Per Common Share (Tables)

12 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

Summary of Earnings Per Share Basic and Diluted

Computations of basic and diluted net income per common share for the years ended December 31, 2016, 2015 and 2014, are as follows:

(In millions, except per share data)	2016		2015		2014
Net income	$	249.8	$	237.2	$	209.4
Basic net income per common share:
Weighted average common shares outstanding		92.8		95.8		96.8
Basic net income per common share	$	2.69	$	2.48	$	2.16
Diluted net income per common share:
Weighted average common shares outstanding — Basic		92.8		95.8		96.8
Plus incremental shares from assumed conversions:
Restricted stock units		0.4		0.5		0.7
Stock options		1.0		0.9		1.2
Weighted average common shares outstanding — Diluted		94.2		97.2		98.7
Diluted net income per common share	$	2.65	$	2.44	$	2.12
Anti-dilutive shares outstanding, excluded from computation		0.4		—		0.2