CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues:
Revenue	$ 8,552	$ 11,863	$ 100,112	$ 28,117
Costs and expenses:
Cost of revenues	61	61	190	158
Sales and marketing	1,664	3,376	4,454	10,142
Research and development	2,110	3,116	7,152	9,138
General and administrative	9,880	10,753	31,669	41,885
Total costs and expenses	13,715	17,306	43,465	61,323
Operating income (loss)	(5,163)	(5,443)	56,647	(33,206)
Interest and other income	545	200	1,151	504
Income (loss) before provision for income taxes	(4,618)	(5,243)	57,798	(32,702)
Provision for income taxes	(22)	(44)	(313)	(295)
Net income (loss)	$ (4,640)	$ (5,287)	$ 57,485	$ (32,997)
Basic net loss per share (in dollars per share)	$ (0.15)	$ (0.18)	$ 1.89	$ (1.13)
Shares used in calculating basic net income (loss) per share (in shares)	30,780	29,245	30,340	29,155
Diluted net loss per share (in dollars per share)	$ (0.15)	$ (0.18)	$ 1.83	$ (1.13)
Shares used in computation of diluted net income (loss) per share (in shares)	30,780	29,245	31,334	29,155
Other comprehensive income (loss), net of tax:
Change in unrealized gains (losses) on short-term investments	$ (2)	$ 10	$ 8	$ (14)
Total other comprehensive income (loss)	(2)	10	8	(14)
Total comprehensive income (loss)	(4,642)	(5,277)	57,493	(33,011)
Royalty and license
Revenues:
Revenue	8,462	11,636	99,789	27,427
Development, services, and other revenue
Revenues:
Revenue	$ 90	$ 227	$ 323	$ 690