Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities
Net loss	$ (40,017)	$ (29,181)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	1,567	1,241
Amortization of intangible assets	160	160
Stock-based compensation expense	3,032	2,910
Amortization of premiums on marketable securities, net	173	412
Amortization of debt issuance costs	378	328
Amortization of right-of-use assets	160	180
Goodwill impairment	12,026	0
Change in fair value of contingent consideration	7	(1,153)
Changes in operating assets and liabilities:
Accounts receivable	655	(317)
Inventory	(1,212)	(879)
Prepaid expenses and other current assets	(3,487)	1,104
Other assets	120	(250)
Accounts payable	(2,641)	(2,091)
Accrued liabilities	1,532	1,500
Operating lease liabilities	(14)	(237)
Other long-term liabilities	(48)	0
Net cash used in operating activities	(27,609)	(26,273)
Cash flows from investing activities
Purchases of available-for-sale marketable securities	0	(9,135)
Sales of available-for-sale marketable securities	2,500	0
Maturities of available-for-sale marketable securities	14,587	25,000
Purchases of property and equipment	(1,088)	(3,693)
Net cash provided by investing activities	15,999	12,172
Cash flows from financing activities
Payment of contingent consideration	(290)	(2,547)
Proceeds from stock options exercises	66	169
Proceeds from employee stock purchase plan	182	0
Net cash used in financing activities	(42)	(2,378)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(100)	(124)
Net change in cash, cash equivalents and restricted cash	(11,752)	(16,603)
Cash, cash equivalents and restricted cash, at the beginning of the period	24,221	25,384
Cash, cash equivalents and restricted cash, at the end of the period	12,469	8,781
Supplemental disclosure of cash flow information:
Cash paid for income taxes	0	35
Cash paid for interest	1,025	1,125
Supplemental disclosure of noncash investing and financing activities:
Change in unrealized loss on marketable securities	57	(6)
Change in unpaid purchases of property and equipment	(97)	(67)
Escrow release	$ 17	$ 0