Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for Bad Debts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 64,654	$ 60,535	$ 51,114
Charged to Expense / Reduction in Revenue	39,312	20,255	18,965
Charged (Credited) to Other Accounts	0	0	0
Deductions	(31,651)	(16,136)	(9,544)
Balance at End of Period	72,315	64,654	60,535
Allowance for Sales Returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	132,883	157,830	129,205
Charged to Expense / Reduction in Revenue	16,748	18,861	47,229
Charged (Credited) to Other Accounts	0	0	0
Deductions	(63,832)	(43,808)	(18,604)
Balance at End of Period	85,799	132,883	157,830
Tax Valuation Allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	5,293	4,350	21,815
Charged to Expense / Reduction in Revenue	0	943	0
Charged (Credited) to Other Accounts	0	0	(662)
Deductions	(943)	0	(16,803)
Balance at End of Period	$ 4,350	$ 5,293	$ 4,350