CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Balance at Dec. 31, 2012	$ 553,413	$ 114	$ 2,432,790	$ (1,879,026)	$ (465)
Balance, Shares at Dec. 31, 2012		114,193
Net income (loss)	37,027			37,027
Other comprehensive income, net of tax	256				256
Issuance of Common Stock under option, stock award and purchase plans	5,186	$ 3	5,183
Issuance of Common Stock under option, stock award and purchase plans, Shares		3,482
Repurchase of Common Stock	(116,529)	$ (18)	(116,511)
Repurchase of Common Stock, Shares		(18,262)
Stock-based compensation	16,089		16,089
Excess tax benefits increase (decrease) from Share-based Compensation, Net	(1,276)		(1,276)
Balance at Dec. 31, 2013	494,166	$ 99	2,336,275	(1,841,999)	(209)
Balance, Shares at Dec. 31, 2013		99,413
Net income (loss)	(46,248)			(46,248)
Other comprehensive income, net of tax	(1,771)				(1,771)
Issuance of Common Stock under option, stock award and purchase plans	1,106	$ 2	1,104
Issuance of Common Stock under option, stock award and purchase plans, Shares		2,181
Repurchase of Common Stock	(93,128)	$ (13)	(93,115)
Repurchase of Common Stock, Shares		(13,894)
Stock-based compensation	17,287		17,287
Excess tax benefits increase (decrease) from Share-based Compensation, Net	401		401
Balance at Dec. 31, 2014	371,813	$ 88	2,261,952	(1,888,247)	(1,980)
Balance, Shares at Dec. 31, 2014		87,700
Net income (loss)	(15,661)			(15,661)
Other comprehensive income, net of tax	(2,438)				(2,438)
Issuance of Common Stock under option, stock award and purchase plans	5,673	$ 3	5,670
Issuance of Common Stock under option, stock award and purchase plans, Shares		2,855
Repurchase of Common Stock	(72,863)	$ (15)	(72,848)
Repurchase of Common Stock, Shares		(14,540)
Stock-based compensation	15,582		15,582
Conversion feature of convertible notes due 2020	26,062
Balance at Dec. 31, 2015	$ 328,168	$ 76	$ 2,236,418	$ (1,903,908)	$ (4,418)
Balance, Shares at Dec. 31, 2015		76,015