Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2012

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of the total compensation expense and associated recognized income tax benefits

	Three Months Ended September 30,						Nine Months Ended September 30,
	2012			2011			2012			2011
Compensation expense	$	7.3		$	7.8		$	22.3		$	24.4
Income tax benefit	(2.8		)	(3.0		)	(8.6		)	(9.4		)
Total	$	4.5		$	4.8		$	13.7		$	15.0