Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue:
Total revenue	$ 17,666	$ 12,197	$ 60,299	$ 14,122
Cost of revenue:
Total cost of revenue	17,302	10,212	54,296	12,080
Gross margin	364	1,985	6,003	2,042
Operating expenses:
Research and development	4,347	3,616	12,506	9,781
Selling and marketing	3,384	2,510	10,024	5,453
General and administrative	16,721	7,502	37,070	22,116
Total operating expenses	24,452	13,628	59,600	37,350
Loss from operations	(24,088)	(11,643)	(53,597)	(35,308)
Interest income	2	1	6	3
Interest expense	(1,974)	(1,843)	(5,758)	(5,372)
Other (expense) income, net	(6,792)	2,269	(307)	(6,853)
Loss before provision for income taxes	(32,852)	(11,216)	(59,656)	(47,530)
Provision for income taxes	0	0	0	0
Net loss and comprehensive loss	(32,852)	(11,216)	(59,656)	(47,530)
Amortization of beneficial conversion feature related to Series A convertible preferred stock	0	0	(2,728)	0
Net loss attributable to common stockholders, basic and diluted	$ (32,852)	$ (11,216)	$ (62,384)	$ (47,530)
Net loss per share, basic and diluted	$ (0.39)	$ (0.19)	$ (0.82)	$ (0.85)
Weighted-average common shares used to compute net loss per share attributable to common stockholders, basic and diluted	84,920,996	59,061,149	76,185,346	56,064,562
Product
Revenue:
Total revenue	$ 16,492	$ 11,358	$ 57,237	$ 11,358
Cost of revenue:
Total cost of revenue	15,199	9,728	49,564	10,322
Service
Revenue:
Total revenue	1,056	721	2,706	2,408
Cost of revenue:
Total cost of revenue	2,103	484	4,732	1,758
Distribution Rights
Revenue:
Total revenue	$ 118	$ 118	$ 356	$ 356