CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Operating Activities
Net loss	$ (17,618)	$ (15,673)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	4,677	4,258
Depreciation and amortization	4,575	1,442
Amortization of marketable securities (discount) premium	(114)	1,150
Other noncash expense	234	139
Changes in operating assets and liabilities:
Accounts receivable	(379)	810
Inventories	1,650	16
Prepaid expenses and other current assets, deposits and other assets	(12,852)	(2,367)
Accounts payable, accrued expenses and non-current liabilities	381	(2,269)
Net cash used in operating activities	(19,446)	(12,494)
Investing Activities
Acquisitions of property, plant and equipment	(11,434)	(31,218)
Acquisition of patent portfolio	0	(10)
Proceeds from sale and maturity of marketable securities	135,550	71,082
Proceeds from sale of property, plant and equipment	67	0
Purchase of marketable securities	0	(31,993)
Net cash provided by investing activities	124,183	7,861
Financing Activities
Proceeds from exercise of warrants	0	3
Net settlement of common stock under stock plans	0	(220)
Payment of debt	(39)	(103)
Payment of finance lease liabilities	(23)	0
Net cash used in financing activities	(62)	(320)
Net increase (decrease) in cash and cash equivalents	104,675	(4,953)
Cash, cash equivalents and restricted cash at beginning of period	315,376	136,033
Cash, cash equivalents and restricted cash at end of period	420,051	131,080
Schedule of cash, cash equivalents and restricted cash
Cash and cash equivalents	342,283	44,626
Restricted cash (current)	1,032	16,216
Non-current restricted cash	76,736	70,238
Total cash, cash equivalents and restricted cash	420,051	131,080
Supplemental disclosures of cash and non-cash investing and financing transactions
Cash paid for interest, net of amounts capitalized	515	(514)
Non-cash purchase of property, plant and equipment	$ 13,277	$ 7,530