Consolidated Statements Of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common stock	Additional paid-in capital	Retained deficit	Foreign currency translation adjustments	Available-for-sale investments-Change in net unrealized gains	Defined benefit pension adjustments
Balance (in shares) at Dec. 31, 2012		138,458
Balance at Dec. 31, 2012	$ 694,799	$ 1,385	$ 809,514	$ (157,038)	$ 41,997	$ 0	$ (1,059)
Shares issued under stock plans (in shares)		1,882
Shares issued under stock plans	7,685	$ 18	7,667	0	0	0	0
Share-based compensation expense	7,928	$ 0	7,928	0	0	0	0
Repurchase and retirement of common stock (in shares)		(1,606)
Repurchase and retirement of common stock	(15,494)	$ (16)	(9,391)	(6,087)	0	0	0
Tax benefit associated with stock plans	3,914	0	3,914	0	0	0	0
Pension liability adjustment	202	0	0	0	0	0	202
Unrealized gain (loss) on available-for-sale investments	0
Reclassification of cumulative translation adjustment associated with liquidated subsidiaries	(787)	0	0	0	(787)	0	0
Foreign currency translation	(17,504)	0	0	0	(17,504)	0	0
Net income	74,526	$ 0	0	74,526	0	0	0
Balance (in shares) at Dec. 31, 2013		138,734
Balance at Dec. 31, 2013	756,843	$ 1,387	819,632	(88,599)	25,280	0	(857)
Shares issued under stock plans (in shares)		1,059
Shares issued under stock plans	1,080	$ 11	1,069	0	0	0	0
Share-based compensation expense	8,887	0	8,887	0	0	0	0
Tax benefit associated with stock plans	842	0	842	0	0	0	0
Pension liability adjustment	(150)	0	0	0	0	0	(150)
Unrealized gain (loss) on available-for-sale investments	(1,884)
Foreign currency translation	(26,948)	0	0	0	(26,948)	0	0
Net income	7,887	$ 0	0	7,887	0	0	0
Balance (in shares) at Dec. 31, 2014		139,793
Balance at Dec. 31, 2014	748,441	$ 1,398	830,430	(80,712)	(1,668)	0	(1,007)
Shares issued under stock plans (in shares)		923
Shares issued under stock plans	1,756	$ 9	1,747	0	0	0	0
Share-based compensation expense	11,033	0	11,033	0	0	0	0
Tax benefit associated with stock plans	5,457	0	5,457	0	0	0	0
Pension liability adjustment	(142)	0	0	0	0	0	(142)
Unrealized gain (loss) on available-for-sale investments	611	0	0	0	0	611	0
Foreign currency translation	(44,569)	0	0	0	(44,569)	0	0
Net income	80,296	$ 0	0	80,296	0	0	0
Balance (in shares) at Dec. 31, 2015		140,716
Balance at Dec. 31, 2015	$ 802,883	$ 1,407	$ 848,667	$ (416)	$ (46,237)	$ 611	$ (1,149)