Schedule II - Valuation Accounts and Reserves (Details) (Allowance for Doubtful Accounts [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning balance	$ 237,339		$ 228,917		$ 238,206
Provision for doubtfull accounts	268,615		279,592		291,737
Net deductions and other	270,207	[1]	271,170	[1]	301,026	[1]
Ending balance	$ 235,747		$ 237,339		$ 228,917

[1] Primarily represents the write-off of accounts receivable, net of recoveries.