Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue:
Total revenue	$ 57,017	$ 87,782	$ 80,962
Cost of revenue:
Total cost of revenue	61,076	93,260	74,359
Gross margin	(4,059)	(5,478)	6,603
Operating expenses:
Research and development	25,008	23,794	16,520
Selling and marketing	15,181	25,806	15,062
General and administrative	61,729	65,717	50,113
Total operating expenses	101,918	115,317	81,695
Loss from operations	(105,977)	(120,795)	(75,092)
Interest income	791	1,721	8
Interest expense	(3,307)	(4,327)	(7,701)
Other income (expense), net	585	3,202	6,389
Loss before provision for income taxes	(107,908)	(120,199)	(76,396)
Provision for income taxes	0	0	0
Net loss and comprehensive loss	(107,908)	(120,199)	(76,396)
Amortization of beneficial conversion feature related to Series A convertible preferred stock	0	0	(2,728)
Net loss attributable to common stockholders, basic and diluted	$ (107,908)	$ (120,199)	$ (79,124)
Net loss per share, basic and diluted	$ (0.73)	$ (1.18)	$ (0.98)
Weighted-average common shares used to compute net loss per share attributable to common stockholders, basic and diluted	147,895,561	102,001,954	81,123,140
Product
Revenue:
Total revenue	$ 42,742	$ 79,504	$ 76,626
Cost of revenue:
Total cost of revenue	49,347	80,446	66,522
Service
Revenue:
Total revenue	13,800	7,803	3,861
Cost of revenue:
Total cost of revenue	11,729	12,814	7,837
Distribution Rights
Revenue:
Total revenue	$ 475	$ 475	$ 475