Immaterial Corrections (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011		Jun. 30, 2012	Jun. 30, 2011
Immaterial Corrections Income Statement
Costs of sales	$ 393.8	$ 376.4		$ 797.8	$ 741.4
Gross profit	173.7	176.0		346.6	344.1
Sales and marketing expenses	46.9	43.9		95.1	85.3
General and administrative expenses	37.9	48.2		91.9	92.5
Operating income (loss)	57.7	46.6		94.2	36.9
Income (loss) from continuing operations before income tax expense	54.3	28.4		89.2	(6.7)
Income tax expense (benefit)	37.6	9.7		62.3	(3.9)
Income (loss) from continuing operations	16.7	18.7		26.9	(2.8)
Income (loss) from discontinued operations	0.1	151.0		(6.9)	293.8
Net income	16.8	169.7		20.0	291.0
As Previously Reported with Reclassification for Discontinued Operations [Member]
Immaterial Corrections Income Statement
Costs of sales		376.6			741.0
Gross profit		175.8			344.5
Sales and marketing expenses		44.0			85.1
General and administrative expenses		44.4			92.1
Operating income (loss)		50.1			37.9
Income (loss) from continuing operations before income tax expense		31.9			(5.7)
Income tax expense (benefit)		11.4			(3.5)
Income (loss) from continuing operations		20.5			(2.2)
Income (loss) from discontinued operations		147.2			294.0
Net income		167.7			291.8
Adjustments [Member]
Immaterial Corrections Income Statement
Costs of sales		(0.2)			0.4
Gross profit		0.2			(0.4)
Sales and marketing expenses		(0.1)			0.2
General and administrative expenses		3.8			0.4
Operating income (loss)		(3.5)			(1.0)
Income (loss) from continuing operations before income tax expense		(3.5)			(1.0)
Income tax expense (benefit)		(1.7)			(0.4)
Income (loss) from continuing operations		(1.8)			(0.6)
Income (loss) from discontinued operations		3.8	[1]		(0.2)
Net income		2.0			(0.8)
As Adjusted and with Reclassification for Discontinued Operations [Member]
Immaterial Corrections Income Statement
Costs of sales		376.4			741.4
Gross profit		176.0			344.1
Sales and marketing expenses		43.9			85.3
General and administrative expenses		48.2			92.5
Operating income (loss)		46.6			36.9
Income (loss) from continuing operations before income tax expense		28.4			(6.7)
Income tax expense (benefit)		9.7			(3.9)
Income (loss) from continuing operations		18.7			(2.8)
Income (loss) from discontinued operations		151.0			293.8
Net income		$ 169.7			$ 291.0

[1] Shares issued and outstanding include unvested restricted common stock of 0.2 at June 30, 2012 and 0.5 at December 31, 2011.