Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2011

Earnings Per Share [Abstract]

Computation of basic and diluted net income per common share

	Three Months Ended				Six Months Ended
	June 30				June 30
	2011		2010		2011		2010
Numerator:
Net income	$	26.4	$	21.5	$	46.3	$	40.2
Numerator for basic earnings per share — income available to common shareholders	$	26.4	$	21.5	$	46.3	$	40.2
Effect of dilutive securities:
After-tax interest expense on convertible securities		—		—		—		0.2
Numerator for diluted earnings per share — income available to common shareholders	$	26.4	$	21.5	$	46.3	$	40.4
Denominator:
Denominator for basic earnings per share — weighted average shares		46.4		46.2		46.4		46.1
Effect of dilutive securities:
Equity compensation plans		0.7		0.4		0.6		0.4
Convertible preferred stock		0.1		0.1		0.1		0.1
Convertible securities		—		—		—		0.5
Denominator for diluted earnings per share — adjusted weighted average and assumed conversion		47.2		46.7		47.1		47.1
Basic earnings per share	$	0.57	$	0.47	$	1.00	$	0.87
Diluted earnings per share	$	0.56	$	0.46	$	0.98	$	0.86