Earnings Per Common Share (Tables)

3 Months Ended

Mar. 31, 2013

Earnings Per Common Share [Abstract]

Earnings per share

(in millions, except per common shares amounts)

	Three Months Ended
	March 31,
	2013		2012
Numerator:
Net income	$	12.5	$	56.2
Denominator:
Denominator for basic earnings per common share-weighted average shares		60.0		63.9
Effect of dilutive securities:
Employee stock-based compensation		1.2		1.8
Denominator for diluted earnings per common share-adjusted weighted average shares		61.2		65.7
Basic earnings per common share	$	0.21	$	0.88
Diluted earnings per common share	$	0.20	$	0.86