CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data	Mar. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
CONSOLIDATED BALANCE SHEETS
Receivables, allowance for doubtful accounts (in dollars)	$ 21,323	$ 19,708	$ 21,268
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Common Stock, shares authorized	3,000	3,000	3,000
Common Stock, shares issued	100	100	100
Common Stock, shares outstanding	100	100	100