CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenue:
Royalties		$ 62,835	$ 62,387	$ 125,712	$ 129,350
Contract and other revenue		13,666	10,425	23,471	16,376
Total revenue		76,501	72,812	149,183	145,726
Operating costs and expenses:
Cost of revenue	[1]	14,089	12,137	26,296	22,893
Research and development	[1]	28,753	29,188	57,280	57,722
Sales, general and administrative	[1]	21,789	17,339	44,884	35,841
Gain from sale of intellectual property		0	(896)	0	(3,156)
Gain from settlement		(138)	(510)	(579)	(1,020)
Total operating costs and expenses		64,493	57,258	127,881	112,280
Operating income (loss)		12,008	15,554	21,302	33,446
Interest income and other income (expense), net		1,138	203	1,380	335
Interest expense		(3,163)	(3,091)	(6,304)	(6,174)
Interest and other income (expense), net		(2,025)	(2,888)	(4,924)	(5,839)
Income before income taxes		9,983	12,666	16,378	27,607
Provision for (benefit from) income taxes		6,107	5,805	10,624	11,244
Net Income (Loss)		$ 3,876	$ 6,861	$ 5,754	$ 16,363
Net income per share:
Earnings Per Share, Basic		$ 0.04	$ 0.06	$ 0.05	$ 0.14
Earnings Per Share, Diluted		$ 0.03	$ 0.06	$ 0.05	$ 0.14
Weighted average shares used in per share calculation:
Basic (in shares)		109,904	116,027	109,818	115,683
Diluted (in shares)		112,061	120,939	112,202	119,225

[1] Includes stock-based compensation