Provision For Doubtful Accounts (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Provision For Doubtful Accounts [Abstract]
Provision for doubtful accounts	$ 3,700	$ 2,600	$ 9,483	$ 7,179	[1]

[1] As Revised (Note 2)