Condensed Consolidated Statements of Operations - 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:
Revenues	$ 23,562	$ 11,812	$ 57,615	$ 23,490
Operating expenses:
Research and development	28,810	18,425	81,612	46,351
General and administrative	10,993	6,422	32,381	19,734
Total operating expenses	39,803	24,847	113,993	66,085
Loss from operations	(16,241)	(13,035)	(56,378)	(42,595)
Interest and other income, net	3,398	681	6,708	1,118
Net loss	$ (12,843)	$ (12,354)	$ (49,670)	$ (41,477)
Basic and diluted net loss per share	$ (0.13)	$ (0.15)	$ (0.52)	$ (0.55)
Shares used in computing basic and diluted net loss per share	101,725	83,750	95,165	75,814
Collaboration Agreements [Member]
Revenues:
Revenues	$ 23,538	$ 11,759	$ 57,378	$ 23,042
Research Grants [Member]
Revenues:
Revenues	$ 24	$ 53	$ 237	$ 448

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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