Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance For Doubtful Accounts [Member]
Movement In Valuation Allowances And Reserves [Roll Forward]
Valuation allowance and qualifying accounts, beginning balance	$ 55,917	$ 63,098	$ 74,660
Charges to costs, expenses and other	20,242	11,715	13,723
Write-off of accounts receivable	28,492	14,082	27,345
Adjustments and other	734	(4,814)	2,060
Valuation allowance and qualifying accounts, ending balance	48,401	55,917	63,098
Valuation Allowance Of Deferred Tax Assets [Member]
Movement In Valuation Allowances And Reserves [Roll Forward]
Valuation allowance and qualifying accounts, beginning balance	183,686	193,052	193,259
Charges to costs, expenses and other	149,107	14,309	8,548
Reversal	(5)	(21,727)	(5,235)
Adjustments and other	(5,165)	(1,948)	(3,520)
Valuation allowance and qualifying accounts, ending balance	$ 327,623	$ 183,686	$ 193,052