CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY AND COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	Total	Common stock:	Additional paid-in capital:	Accumulated (losses) earnings:	Treasury stock:	Accumulated other comprehensive (loss):	Comprehensive (loss) income:
Beginning balance at Dec. 31, 2008		$ 926	$ 628,356	$ 58,059	$ (42,586)	$ (48,926)
Change in the number of shares of Class A common stock outstanding
Issuance of Class A common stock in connection with employee stock purchase plan		1	797
Issuance of Class A common stock in connection with stock options, restricted stock units and warrants		17	1,662
Purchases of Class A common stock		(5)			(5,539)
Repurchase of stock options			(1,892)
Stock-based compensation			34,589
Tax benefit from employee stock options and restricted stock units			(1,236)
Tax benefit from repurchase of convertible debentures			3,141
Unwind of bond hedge			1,335
Deferred compensation			(5,456)
Convertible debt feature in accordance with New Convertible Debt Guidance			9,948
Equity issuance costs per New Convertible Debt guidance			0
Comprehensive income (loss):
Net loss	(39,879)			(39,879)			(39,879)
Other comprehensive (loss) income
Pension gains and losses, net of tax							(1,410)
Foreign currency translation adjustment							45,304
Effective portion of derivative financial instruments							2,486
Unrealized loss on investments, net of tax							(38)
Other comprehensive (loss) income						46,342	46,342
Comprehensive (loss) income							6,463
Ending balance at Dec. 31, 2009	619,758	939	651,348	18,180	(48,125)	(2,584)
Change in the number of shares of Class A common stock outstanding
Issuance of Class A common stock in connection with employee stock purchase plan		1	664
Issuance of Class A common stock in connection with stock options, restricted stock units and warrants		35	913
Purchases of Class A common stock					(26,335)
Repurchase of stock options			(772)
Stock-based compensation			22,807
Tax benefit from employee stock options and restricted stock units			(4,024)
Tax benefit from repurchase of convertible debentures			0
Unwind of bond hedge			0
Deferred compensation			3,755
Convertible debt feature in accordance with New Convertible Debt Guidance			0
Equity issuance costs per New Convertible Debt guidance			0
Comprehensive income (loss):
Net loss	(149,201)			(149,201)			(149,201)
Other comprehensive (loss) income
Pension gains and losses, net of tax							447
Foreign currency translation adjustment							(16,325)
Effective portion of derivative financial instruments							935
Unrealized loss on investments, net of tax							0
Other comprehensive (loss) income						(14,943)	(14,943)
Comprehensive (loss) income							(164,144)
Ending balance at Dec. 31, 2010	452,658	975	674,691	(131,021)	(74,460)	(17,527)
Change in the number of shares of Class A common stock outstanding
Issuance of Class A common stock in connection with employee stock purchase plan		1	611
Issuance of Class A common stock in connection with stock options, restricted stock units and warrants		6	(2,971)
Purchases of Class A common stock					0
Repurchase of stock options			0
Stock-based compensation			21,538
Tax benefit from employee stock options and restricted stock units			(435)
Tax benefit from repurchase of convertible debentures			0
Unwind of bond hedge			0
Deferred compensation			166
Convertible debt feature in accordance with New Convertible Debt Guidance			0
Equity issuance costs per New Convertible Debt guidance			0
Comprehensive income (loss):
Net loss	(12,570)			(12,570)			(12,570)
Other comprehensive (loss) income
Pension gains and losses, net of tax							(5,219)
Foreign currency translation adjustment							(11,860)
Effective portion of derivative financial instruments							1,862
Unrealized loss on investments, net of tax							(73)
Other comprehensive (loss) income						(15,290)	(15,290)
Comprehensive (loss) income							(27,860)
Ending balance at Dec. 31, 2011	$ 443,714	$ 982	$ 693,600	$ (143,591)	$ (74,460)	$ (32,817)