CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating activities:
Net loss	$ (7,495)	$ (7,091)
Adjustments to reconcile net loss to net cash flows from operating activities:
Depreciation and amortization expense	1,158	873
Stock-based compensation expense	8,731	9,531
Amortization of premiums and discounts on marketable securities	(290)	194
Amortization of debt issuance costs	54	0
Non-cash lease costs	1,112	1,076
Other	12	4
Changes in operating assets and liabilities:
Inventory	616	(1,004)
Accounts receivable	8,180	5,582
Other current assets	263	(847)
Accounts payable	(274)	(219)
Accrued expenses	(3,079)	(3,734)
Operating lease liabilities	(1,128)	(897)
Net cash provided by operating activities	7,860	3,468
Investing activities:
Purchases of investments	(9,787)	(12,629)
Sales and maturities of investments	21,500	5,041
Expenditures for property and equipment	(1,413)	(3,081)
Purchases of intangible assets	(7,500)	0
Net cash provided by (used in) investing activities	2,800	(10,669)
Financing activities:
Net proceeds from common stock issuance	2,225	1,465
Payments on employee’s behalf for taxes related to vesting of restricted stock unit awards	(2,097)	(943)
Other	(21)	(19)
Net cash provided by financing activities	107	503
Net increase (decrease) in cash, cash equivalents, and restricted cash	10,767	(6,698)
Cash, cash equivalents, and restricted cash at beginning of period	51,067	68,541
Cash, cash equivalents, and restricted cash at end of period	61,834	61,843
Supplemental disclosure of cash flow information:
Right-of-use asset and lease liability recognized	419	0
Additions to property and equipment included in accounts payable	2,282	317
Restricted stock held for employee tax remittance included in accounts payable	0	480
Reconciliation of amounts within the condensed consolidated balance sheets:
Cash and cash equivalents	61,834	55,659
Restricted cash	0	6,184
Total cash, cash equivalents, and restricted cash at end of period	$ 61,834	$ 61,843