Net Income per Common Share (Tables)

3 Months Ended

Mar. 31, 2019

Earnings Per Share [Abstract]

Summary of Earnings Per Share Basic and Diluted

	Quarter Ended March 31,
(In millions, except per share data)	2019		2018
Basic net income per common share:
Net income	$	72.2	$	61.6
Weighted average common shares outstanding		85.0		90.0
Basic net income per common share	$	0.85	$	0.68
Diluted net income per common share:
Net income		72.2		61.6
Weighted average common shares outstanding — Basic		85.0		90.0
Plus incremental shares from assumed conversions:
Restricted stock units		0.4		0.5
Stock options		0.6		0.7
Weighted average common shares outstanding — Dilutive		86.0		91.2
Diluted net income per common share	$	0.84	$	0.68