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
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 110,610		$ 110,046		$ 89,802
Charged to expense	(8,035)		588		20,320
Deductions from reserves	(358)		(24)		(76)
Balance and end of period	102,217		110,610		110,046
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	1,043		2,556		1,108
Charged to expense	52		12		1,524
Deductions from reserves	(358)		(1,525)		(76)
Balance and end of period	737		1,043		2,556
Allowance for Notes Receivable [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	1,501	[1]	0	[1]
Charged to expense	(513)		0	[1]
Deductions from reserves	0		1,501	[1]
Balance and end of period	988		1,501	[1]
Valuation Allowance on Deferred Tax Assets [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	108,066		107,490		88,694
Charged to expense	(7,574)		576		18,796
Deductions from reserves	0		0		0
Balance and end of period	$ 100,492		$ 108,066		$ 107,490

[1] Reflects reclassification from allowance for doubtful accounts on trade receivables to allowance for notes receivable.