Valuation And Qualifying Accounts

12 Months Ended

Dec. 31, 2011

Valuation And Qualifying Accounts [Abstract]

Schedule Of Valuation And Qualifying Accounts

14. VALUATION AND QUALIFYING ACCOUNTS

The following table summarizes the activity and ending balances in our allowance for doubtful accounts and estimated revenue adjustments (amounts in millions):

Allowance for Doubtful Accounts

Year end	Balance at beginning of Year		Provision for doubtful accounts (1)		Write-offs			Acquired through acquisitions		Balance at end of Year
2011	$	21.0	$	13.7	$	(17.3	)	$	—	$	17.4
2010		26.4		19.2		(24.6	)		—		21.0
2009		27.1		20.2		(21.1	)		0.2		26.4

(1) Includes $0.2 million, $0.5 million and $0.5 million from discontinued operations for the years ended December 31, 2011, 2010 and 2009, respectively.

Estimated Revenue Adjustments

Year end	Balance at beginning of Year		Provision for estimated revenue adjustments (1)		Write-offs			Acquired through acquisitions		Balance at end of Year
2011	$	6.5	$	12.1	$	(11.8	)	$	—	$	6.8
2010		8.7		7.0		(9.2	)		—		6.5
2009		7.2		8.8		(7.3	)		—		8.7

(1) Includes $0.3 million, $0.5 million and $0.2 million from discontinued operations for the years ended December 31, 2011, 2010 and 2009, respectively.