Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue
Laboratory service revenue	$ 99,376	$ 39,437	$ 1,504
License fees			294
Total revenue	99,376	39,437	1,798
Cost of sales	45,195	24,501	4,325
Gross margin	54,181	14,936	(2,527)
Operating expenses:
Research and development	33,473	33,914	28,669
General and administrative	76,898	57,950	30,435
Sales and marketing	112,826	82,140	38,908
Total operating expenses	223,197	174,004	98,012
Loss from operations	(169,016)	(159,068)	(100,539)
Other income (expense)
Investment income	2,018	1,271	542
Interest expense	(213)	(6)	(51)
Total other income	1,805	1,265	491
Net loss	$ (167,211)	$ (157,803)	$ (100,048)
Net loss per share-basic and diluted (in dollars per share)	$ (1.63)	$ (1.71)	$ (1.25)
Weighted average common shares outstanding-basic and diluted (in shares)	102,335	92,135	80,232