Condensed Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities
Net loss	$ (32,077)	$ (21,233)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	922	482
Stock-based compensation expense	11,139	6,942
Amortization of premiums (accretion of discounts) on investments, net	(64)	387
Amortization of debt discount and debt issuance costs	91	80
Amortization of right-of-use asset	496	373
Non-cash interest expense	474	(7)
Loss on extinguishment of debt	245
Loss on disposal of property and equipment	175
Change in provision for doubtful accounts receivable	(3)
Provision for excess and obsolete inventories	(3)	50
Changes in assets and liabilities:
Accounts receivable	(3,944)	(2,677)
Inventories	239	(456)
Prepaid expenses and other current assets	(1,242)	(3,227)
Other assets	(37)	(74)
Accounts payable	1,076	(833)
Accrued liabilities	(2,620)	(482)
Other liabilities	2	(333)
Net cash used in operating activities	(25,131)	(21,008)
Cash flows from investing activities
Purchases of property and equipment	(3,049)	(874)
Purchases of investments	(21,173)
Proceeds from maturity of investments		51,300
Net cash provided by (used in) investing activities	(24,222)	50,426
Cash flows from financing activities
Proceeds from issuance of common stock	1,729	2,965
Proceeds from long-term debt	75,000
Principal repayment of debt	(49,000)
Payments of debt issuance costs	(970)
Net cash provided by financing activities	26,759	2,965
Net change in cash, cash equivalents and restricted cash	(22,594)	32,383
Cash, cash equivalents and restricted cash, beginning of period	110,463	69,776
Cash, cash equivalents and restricted cash, end of period	87,869	102,159
Supplemental disclosure of cash flow information
Cash paid for interest	1,087	1,177
Noncash investing and financing activities:
Accounts payable and accrued liabilities for purchases of property and equipment	105	283
Right-of-use asset obtained in exchange for lease obligation	903	$ 3,398
Unpaid debt issuance costs	$ 119