CONSOLIDATED STATEMENT OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net loss	$ (62,493,000)	$ (77,702,000)	$ (78,208,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,000,000	2,518,000	2,997,000
Amortization of investment discount	98,000	226,000	99,000
Equity-based compensation expense	10,625,000	22,047,000	16,464,000
Amortization of debt discount and issuance costs	474,000	11,542,000	11,168,000
Amortization of debt discount related party	834,000	0	0
Realized loss on available-for-sale securities	0	0	3,000
Unrealized loss on equity investments	211,000	0	0
Loss (gain) on disposal of property and equipment	133,000	(75,000)	785,000
Gain on extinguishment of debt	(3,565,000)	(9,793,000)	0
Inventory write-down	0	4,500,000	0
(Increase) decrease in assets:
Contributions to deferred compensation plan	(298,000)	(484,000)	(357,000)
Accounts receivable	(96,000)	(770,000)	1,592,000
Inventory	(236,000)	(415,000)	(1,356,000)
Prepaid expense and other assets	138,000	1,014,000	(2,087,000)
Increase (decrease) in liabilities:
Accounts payable	2,920,000	273,000	(1,006,000)
Accrued liabilities and other	(861,000)	(469,000)	(909,000)
Accrued interest	(437,000)	(283,000)	0
Accrued interest from related-party	663,000	0	0
Deferred revenue and income	96,000	75,000	105,000
Deferred compensation	66,000	473,000	316,000
Net cash used in operating activities	(48,728,000)	(47,323,000)	(50,394,000)
Cash flows from investing activities:
Purchases of equipment	(554,000)	(603,000)	(1,362,000)
Purchase of marketable securities	(27,506,000)	(30,081,000)	(46,933,000)
Proceeds from sales of marketable securities	0	250,000	0
Maturities of marketable securities	40,477,000	38,738,000	61,901,000
Net cash provided by investing activities	12,417,000	8,304,000	13,606,000
Cash flows from financing activities:
Proceeds from issuance of common and preferred shares, net	32,872,000	42,880,000	359,000
Proceeds from exercise of options	7,000	1,620,000	6,062,000
Proceeds from issuance of common stocks under employee purchase plan	224,000	326,000	0
Proceeds from debt	0	0	5,578,000
Payment of debt	(80,000)	(360,000)	(366,000)
Payments on finance leases	(1,201,000)	0	0
Debt exchange and common stock issuance cost	(192,000)	(1,240,000)	0
Net cash provided by financing activities	31,630,000	43,226,000	11,633,000
Effect of exchange rate on cash	(312,000)	(90,000)	(78,000)
(Decrease) increase in cash and cash equivalents	(4,993,000)	4,117,000	(25,233,000)
Cash and cash equivalents, beginning of period	39,898,000	35,781,000	61,014,000
Cash and cash equivalents, end of period	34,905,000	39,898,000	35,781,000
Non-cash investing activities:
Net transfer of instruments from inventory to property and equipment, net	168,000	688,000	1,525,000
Non-cash financing activities:
Extinguishment of convertible senior notes through issuance of common stock	10,180,000	38,902,000	0
Convertible notes due from related-party extinguished in connection with the exchange transaction, net of deferred issuance costs	49,624,000	0	0
Fair value of new note from related-party issued in connection with the exchange transaction	16,024,000	0	0
Fair value of common stock warrant issued to related-party in connection with exchange transaction	3,753,000	0	0
Capital contribution from related-party in connection with the exchange transaction	29,847,000	0	0
Right-of-use assets obtained in exchange for finance lease obligations	3,096,000	0	0
Supplemental cash flow information:
Interest paid	2,214,000	4,288,000	4,288,000
Income taxes paid, net of refunds	$ 0	$ 0	$ 43,000