Consolidated Statement of Changes in Stockholders' Equity (USD $) In Thousands, except Share data, unless otherwise specified	$0.001 Par Value Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Noncontrolling Interest in Subsidiary [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2011	$ 36	$ 220,654	$ 0	$ (3,313)	$ 2,481	$ 196,869	$ 416,727
Balance (in shares) at Dec. 31, 2011	36,002,698		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Employee equity award plans activity	0	10,310		0	0	0	10,310
Employee equity award plans activity (in shares)	269,852
Non-cash development expenses from joint venture					3,670	0	3,670
Net loss attributable to noncontrolling interest					(5,381)	0	(5,381)
Treasury stock			(5,906)	0	0		(5,906)
Treasury stock (in shares)			(403,158)
Net income					0	23,524	23,524
Foreign currency translations, net of tax				(816)	0	0	(816)
Balance at Dec. 31, 2012	36	230,964	(5,906)	(4,129)	770	220,393	442,128
Balance (in shares) at Dec. 31, 2012	36,272,550		(403,158)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Employee equity award plans activity	1	16,673		0	0	0	16,674
Employee equity award plans activity (in shares)	764,446
Non-cash development expenses from joint venture				0	(347)	0	(347)
Net loss attributable to noncontrolling interest				0	(876)	0	(876)
Treasury stock			(213)	0	0		(213)
Treasury stock (in shares)			(9,795)
Net income				0	0	31,135	31,135
Foreign currency translations, net of tax				664	0	0	664
Balance at Dec. 31, 2013	37	247,637	(6,119)	(3,465)	(453)	251,528	489,165
Balance (in shares) at Dec. 31, 2013	37,036,996		(412,953)				36,624,043
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Employee equity award plans activity	1	26,585		0	0	0	26,586
Employee equity award plans activity (in shares)	1,092,876
Non-cash development expenses from joint venture				0	453	0	453
Net loss attributable to noncontrolling interest							0
Treasury stock			(201)	0	0		(201)
Treasury stock (in shares)			(7,236)
Net income				0	0	36,741	36,741
Foreign currency translations, net of tax				457	0	0	457
Balance at Dec. 31, 2014	$ 38	$ 274,222	$ (6,320)	$ (3,008)	$ 0	$ 288,269	$ 553,201
Balance (in shares) at Dec. 31, 2014	38,129,872		(420,189)				37,709,683