Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue:
Total revenue	$ 10,086	$ 20,862	$ 38,560	$ 71,313
Cost of revenue:
Total cost of revenue	11,150	20,288	42,773	72,857
Gross margin	(1,064)	574	(4,213)	(1,544)
Operating expenses:
Research and development	5,245	5,641	17,793	17,135
Selling and marketing	2,669	7,297	11,585	19,845
General and administrative	16,031	19,381	47,046	49,888
Total operating expenses	23,945	32,319	76,424	86,868
Loss from operations	(25,009)	(31,745)	(80,637)	(88,412)
Interest income	5	484	787	1,391
Interest expense	(1,074)	(1,069)	(3,183)	(2,902)
Other (expense) income, net	(2,047)	11,499	1,224	4,933
Loss before provision for income taxes	(28,125)	(20,831)	(81,809)	(84,990)
Provision for income taxes	0	0	0	0
Net loss and comprehensive loss	$ (28,125)	$ (20,831)	$ (81,809)	$ (84,990)
Net loss per share, basic and diluted	$ (0.19)	$ (0.21)	$ (0.55)	$ (0.87)
Weighted-average common shares used to compute net loss per share attributable to common stockholders, basic and diluted	148,042,972	99,039,789	147,683,344	97,763,964
Product
Revenue:
Total revenue	$ 6,210	$ 18,696	$ 28,295	$ 65,475
Cost of revenue:
Total cost of revenue	8,550	18,521	34,393	63,368
Service
Revenue:
Total revenue	3,758	2,048	9,909	5,482
Cost of revenue:
Total cost of revenue	2,600	1,767	8,380	9,489
Distribution Rights
Revenue:
Total revenue	$ 118	$ 118	$ 356	$ 356