Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2012

Earnings Per Share [Abstract]

Computation of basic and diluted net income per common share

	Three Months Ended March 31
	2012		2011
Numerator:
Net income	$	30.3	$	19.9
Denominator:
Weighted average shares outstanding - basic		46.7		46.3
Effect of dilutive securities:
Equity compensation plans		0.7		0.6
Convertible preferred stock		0.1		0.1
Weighted average shares outstanding - diluted		47.5		47.0
Basic earnings per share	$	0.65	$	0.43
Diluted earnings per share	$	0.64	$	0.42