Condensed Consolidated Statements Of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue:
Royalty and license fees	$ 63,954	$ 91,322	$ 129,486	$ 158,577
Total revenue	63,954	91,322	129,486	158,577
Operating expenses:
Cost of revenue	2,080	1,303	4,404	2,703
Research, development and other related costs	25,170	26,313	51,685	52,325
Selling, general and administrative	30,476	33,003	65,178	74,208
Amortization expense	27,199	28,151	54,365	56,706
Litigation expense	6,635	8,226	13,951	18,204
Total operating expenses	91,560	96,996	189,583	204,146
Operating loss	(27,606)	(5,674)	(60,097)	(45,569)
Interest expense	(6,200)	(7,046)	(12,518)	(13,505)
Other income and expense, net	2,229	220	5,383	266
Loss before taxes	(31,577)	(12,500)	(67,232)	(58,808)
Provision for (benefit from) income taxes	(3,321)	26,557	(5,959)	(8,722)
Net loss	$ (28,256)	$ (39,057)	$ (61,273)	$ (50,086)
Basic and diluted net loss per share:
Basic (in dollars per share)	$ (0.58)	$ (0.79)	$ (1.25)	$ (1.02)
Diluted (in dollars per share)	(0.58)	(0.79)	(1.25)	(1.02)
Cash dividends declared per share (in dollars per share)	$ 0.20	$ 0.20	$ 0.4	$ 0.4
Weighted average number of shares used in per share calculations-basic (in shares)	49,060	49,475	49,110	49,261
Weighted average number of shares used in per share calculations-diluted (in shares)	49,060	49,475	49,110	49,261