Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net loss	$ (47,173)	$ (33,589)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation	4,431	2,654
Stock-based compensation	11,958	10,123
Amortization of operating lease right-of-use assets	1,538	994
Non-cash interest and other expense related to debt and note receivable agreements	32	36
Provision for excess and obsolete inventory	479	330
Loss on disposal and impairment of property and equipment	27	31
Other non-cash	271	0
Changes in operating assets and liabilities:
Trade accounts receivable	12,128	(6,820)
Inventory	(1,539)	(5,710)
Prepaid expenses, other current assets and other assets	1,340	(639)
Trade accounts payable	1,000	4,512
Deferred revenue	(4,400)	2,942
Accrued expenses and other current liabilities	(585)	1,872
Operating lease liabilities	(95)	(831)
Net cash used in operating activities	(20,588)	(24,095)
Cash flows from investing activities:
Purchase of property and equipment	(6,758)	(4,382)
Purchase of marketable securities	(9,372)	0
Net cash used in investing activities	(16,130)	(4,382)
Cash flows from financing activities:
Payment of debt issuance costs	0	(358)
Proceeds from issuance of common stock upon exercise of stock options	766	8,347
Proceeds from issuance of common stock under employee stock purchase plan	610	2,157
Net cash provided by financing activities	1,376	10,146
Net decrease in cash and cash equivalents and restricted cash	(35,342)	(18,331)
Cash and cash equivalents and restricted cash at beginning of period	178,366	233,678
Cash and cash equivalents and restricted cash at end of period	$ 143,024	$ 215,347