CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)
Cash flows from operating activities:
Net income (loss)	$ (48,620)	$ (47,884)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	2,434	2,207
Amortization of investment discount	0	94
Equity-based compensation	4,023	8,179
Loss on disposal of property and equipment	134	74
Unrealized (gain) loss on equity investments	(61)	206
Gain on fair value adjustments	(13,026)	0
Inventory write-down	1,184	0
(Increase) decrease in assets:
Contributions to deferred compensation plan	0	(174)
Accounts receivable	(250)	(73)
Inventory	298	(245)
Prepaid expense and other	956	(491)
Increase (decrease) in liabilities:
Accounts payable	218	1,221
Accrued liabilities and other	67	1,153
Deferred revenue and income	1,139	73
Deferred compensation	194	(49)
Net cash used in operating activities	(32,441)	(39,178)
Cash flows from investing activities:
Purchases of equipment	(925)	(446)
Purchase of marketable securities	0	(27,506)
Maturities of marketable securities	9,695	34,527
Net cash provided by investing activities	8,770	6,575
Cash flows from financing activities:
Payments on finance leases	(1,357)	(1,109)
Proceeds from exercise of options	0	7
Proceeds from issuance of common stock under employee purchase plan	0	184
Proceeds from issuance of 5.00% Notes	10,000	0
Transaction costs related to debt and equity issuances	(3,731)	(192)
Payment of debt	0	(6)
Net cash provided by financing activities	8,912	31,756
Effect of exchange rate on cash	16	(64)
Decrease in cash and cash equivalents	(14,743)	(911)
Cash and cash equivalents, beginning of period	34,905	39,898
Cash and cash equivalents, end of period	20,162	38,987
Non-cash investing activities:
Net transfer of instruments from inventory to property and equipment	343	(78)
Non-cash financing activities:
Capital contribution from the exchange of secured note and accrued interest through the issuance of common stock with related party	25,363	29,847
Exchange of 2.50% Notes and accrued interest for 5.00% Notes	56,893	0
Debt premium on issuance of 5.00% Notes	6,023	0
Derivative liability	38,160	0
2.50% Notes extinguished in connection with exchange transaction	0	49,624
Fair value of new note issued in connection with the exchange transaction	0	16,024
Fair value of common stock warrant issued in connection with the exchange transaction	0	3,753
Extinguishment of derivative liability in connection with extinguishment of 5.00% Notes	380	0
Issuance of common stock in connection with extinguishment of 5.00% Notes	658	0
Supplemental cash flow information:
Interest paid	0	2,214
Convertible Notes
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount and issuance costs	2,060	386
2.50% Convertible Notes Due 2023 | Convertible Notes
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount and issuance costs	182	386
Non-cash financing activities:
Extinguishment of Convertible Senior Notes through issuance of common stock	$ 0	10,180
Interest rate	2.50%
5.00% Convertible Notes Due 2026 | Convertible Notes
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount and issuance costs	$ 1,878	0
Non-cash financing activities:
Extinguishment of Convertible Senior Notes through issuance of common stock	$ 330	0
Interest rate	5.00%
Nonrelated Party
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount and issuance costs	$ 2,060	386
Loss (gain) on extinguishment of debt	6,499	(3,565)
Increase (decrease) in liabilities:
Accrued interest	1,738	(785)
Cash flows from financing activities:
Proceeds from issuance of common stock	0	32,872
Related Party
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount and issuance costs	1,033	275
Loss (gain) on extinguishment of debt	6,755	0
Increase (decrease) in liabilities:
Accrued interest	784	220
Cash flows from financing activities:
Proceeds from issuance of common stock	$ 4,000	$ 0