Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (35,460)	$ (87,126)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	129	1,547
(Gain) loss on sale of property and equipment, net	(12)	59
Noncash lease expense relating to operating lease right-of-use assets	956	1,406
Gain on termination of operating lease, net	(491)	(35)
Impairment, Long-Lived Asset, Held-for-Use	0	9,988
Common stock purchase agreement costs	1,124	0
Inventory write-downs, net of scrapped inventory	161	7,712
Loss on advances to suppliers	0	1,385
Change in fair value of convertible note and warrant liabilities	0	858
Realized loss on instrument-specific credit risk	0	46
Stock-based compensation	9,047	18,071
Amortization of premiums and accretion of discounts on marketable securities, net of change in accrued interest	(611)	(211)
Expected credit losses, net of write-off	35	35
Changes in operating assets and liabilities:
Accounts receivable, net	85	451
Inventories, current and noncurrent, net	245	(2,459)
Prepaid and other current assets	1,490	2,279
Other noncurrent assets	215	284
Accounts payable	156	252
Accrued expenses and other current liabilities	(2,389)	(3,135)
Operating lease liabilities	(955)	(1,528)
Contract liabilities	0	(987)
Other noncurrent liabilities	(345)	383
Net cash used in operating activities	(26,620)	(50,725)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(486)	(1,951)
Proceeds from sale of property and equipment	45	283
Proceeds from redemptions and maturities of marketable securities	32,426	76,350
Purchases of marketable securities	(24,241)	(19,331)
Net cash provided by investing activities	7,744	55,351
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from exercise of stock options	134	455
Proceeds from the issuance of convertible notes	146	0
Payments for convertible note redemptions	0	(6,235)
Taxes paid related to the net share settlement of equity awards	(161)	(1,445)
Proceeds from issuance of common stock under the Common Stock Purchase Agreements	11,080	136
Stock issuance costs related to the Common Stock Purchase Agreements	(1,232)	(3)
Proceeds from issuance of common stock through the Employee Stock Purchase Plan	93	334
Net cash provided by (used in) financing activities	10,060	(6,758)
NET DECREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(8,816)	(2,132)
CASH, CASH EQUIVALENTS AND RESTRICTED CASH—Beginning of period	19,082	21,214
CASH, CASH EQUIVALENTS AND RESTRICTED CASH—End of period	10,266	19,082
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest	0	115
Cash (refunded) paid for income taxes, net	(2)	16
SUPPLEMENTAL DISCLOSURE OF NONCASH INVESTING AND FINANCING ACTIVITIES:
Operating lease liabilities extinguished upon termination of lease	16,325	335
Operating lease right-of-use asset derecognized upon termination of lease	10,371	0
Operating lease right-of-use assets obtained in exchange for lease obligation	753	0
Conversion of convertible notes and accrued interest into Class A common stock	0	3,338
Stock issuance costs included in accounts payable and accrued liabilities	198	0
Stock issuance costs through issuance of common stock	282	0
Proceeds from issuance of common stock in prepaid and other current assets	$ 1,679	$ 0