Condensed Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash Flows From Operating Activities:
Net loss	$ (11,343)	$ (10,925)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount and debt issuance costs	64	61
Depreciation and amortization	2,514	2,668
Non-cash lease expense	161	153
Stock-based compensation expense	1,274	1,523
Change in fair value of contingent consideration liability		(151)
Property and equipment write-downs/disposals		10
Net changes in operating assets and liabilities:
Accounts receivable, net	7	142
Inventory	(1,128)	(1,127)
Prepaid expenses and other current assets	814	997
Other non-current assets	(149)
Accounts payable	942	(550)
Accrued liabilities	(771)	402
Accrued compensation	(559)	(631)
Operating lease liability	(212)	(197)
Net cash used in operating activities	(8,386)	(7,625)
Cash Flows From Investing Activities:
Purchase of property and equipment	(75)	(82)
Net cash used in investing activities	(75)	(82)
Cash Flows From Financing Activities:
Proceeds from issuance of common stock under Share Purchase Agreement, net	26,774
Payment of contingent consideration		(5,000)
Proceeds from issuance of common stock		3
Net cash (used in) provided by financing activities	26,774	(4,997)
Net increase (decrease) in cash, cash equivalents and restricted cash	18,313	(12,704)
Cash, cash equivalents and restricted cash at the beginning of the period	7,811	48,415
Cash, cash equivalents and restricted cash at the end of the period	26,124	35,711
Reconciliation of cash, cash equivalents and restricted cash to balance sheets
Cash and cash equivalents	25,255	27,904
Restricted cash	869	7,807
Cash, cash equivalents and restricted cash in balance sheets	26,124	35,711
Supplemental Disclosure of Cash Flow Information:
Cash paid for interest	986	568
Supplemental Disclosure of Non-cash Items:
Vesting of early exercised stock options	30	39
Purchases of property and equipment included in accounts payable		18
Net reclassification of inventory to property and equipment for customer usage agreements	783	805
Cummulative effect adjustment from adoption of ASU 2016-13	$ 155
Right of use asset acquired under operating lease on the adoption of ASC 842		$ 894