Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Total revenue	$ 70,119	$ 57,017	$ 87,782
Cost of revenue:
Total cost of revenue	69,784	61,076	93,260
Gross profit (loss)	335	(4,059)	(5,478)
Operating expenses:
Research and development	31,849	25,008	23,794
Selling and marketing	16,044	15,181	25,806
General and administrative	56,091	61,729	65,717
Total operating expenses	103,984	101,918	115,317
Loss from operations	(103,649)	(105,977)	(120,795)
Interest income	13	791	1,721
Interest expense	(4,241)	(3,307)	(4,327)
Other income (expense), net	(2,171)	585	3,202
Loss before provision for income taxes	(110,048)	(107,908)	(120,199)
Provision for income taxes	0	0	0
Net loss attributable to common stockholders, basic and diluted	$ (110,048)	$ (107,908)	$ (120,199)
Net loss per share, basic (USD per share)	$ (0.67)	$ (0.73)	$ (1.18)
Net loss per share, diluted (USD per share)	$ (0.67)	$ (0.73)	$ (1.18)
Weighted-average common shares used in computing net loss per share, diluted (in shares)	164,521,064	147,895,561	102,001,954
Weighted-average common shares used in computing net loss per share, basic (in shares)	164,521,064	147,895,561	102,001,954
Product
Revenue:
Total revenue	$ 51,865	$ 42,742	$ 79,504
Cost of revenue:
Total cost of revenue	51,780	49,347	80,446
Service
Revenue:
Total revenue	17,779	13,800	7,803
Cost of revenue:
Total cost of revenue	18,004	11,729	12,814
Distribution rights
Revenue:
Total revenue	$ 475	$ 475	$ 475