Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues
Revenues	$ 14,700	$ 5,306	$ 23,465	$ 177,728
Types of Revenue[Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating Expenses
Cost of revenues	$ 2,494	$ 517	$ 4,450	$ 6,797
Research and development	35,692	18,508	90,378	59,544
General and administrative	12,402	9,008	37,365	25,706
Other operating expenses (income)	8	(2)	(54)	31
Total operating expenses	50,596	28,031	132,139	92,078
Income (loss) from operations	(35,896)	(22,725)	(108,674)	85,650
Other Income
Interest income from licensing	716	109	2,091	8,362
Investment income	431	2,122	37,950	4,177
Total other income	1,147	2,231	40,041	12,539
Income (loss) before income taxes	(34,749)	(20,494)	(68,633)	98,189
Income Tax Benefit (Expense)	165	1,292	364	(2,558)
Net income (loss)	(34,584)	(19,202)	(68,269)	95,631
Other Comprehensive Income (Loss)
Unrealized gain (loss) on available-for-sale securities, net of reclassifications and income tax expense	(108)	(103)	1,043	(159)
Total other comprehensive income (loss)	(108)	(103)	1,043	(159)
Comprehensive income (loss)	(34,692)	(19,305)	(67,226)	95,472
Net income (loss) applicable to common stockholders	$ (34,584)	$ (19,202)	$ (68,269)	$ 95,631
Net income (loss) per share:
Basic	$ (0.94)	$ (0.56)	$ (1.86)	$ 2.94
Diluted	$ (0.94)	$ (0.56)	$ (1.86)	$ 2.67
Weighted-average common shares outstanding:
Basic	36,813	33,988	36,618	32,576
Diluted	36,813	33,988	36,618	35,875