CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jul. 02, 2023
Cash flows used in operating activities:
Net loss	$ (162,444)	$ (137,909)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation, accretion and amortization	30,917	7,100
Stock-based compensation	31,797	44,199
Changes in fair value of common stock warrants	12,540	27,180
Impairment and loss on disposal of long-lived assets	35,107	4,411
Others	172	0
Changes in operating assets and liabilities:
Accounts and notes receivables	669	128
Inventory	(771)	(163)
Prepaid expenses and other assets	(1,562)	3,145
Accounts payable	(8,250)	892
Accrued expenses and compensation	3,465	1,849
Deferred revenue	299	0
Deferred tax liability	(5,366)	0
Other liabilities	1,434	5
Net cash used in operating activities	(61,993)	(49,163)
Cash flows from investing activities:
Purchase of property and equipment	(40,297)	(15,724)
Purchases of investments	(31,812)	(65,736)
Maturities of investments	91,621	0
Net cash provided by (used in) investing activities	19,512	(81,460)
Cash flows from financing activities:
Proceeds from loan borrowing and issuance of Convertible Senior Notes	4,572	172,500
Repayment of debt	(73)	0
Payments of debt issuance costs	0	(5,228)
Purchase of Capped Calls	0	(17,250)
Payroll tax payments for shares withheld upon vesting of RSUs	(3,315)	(1,226)
Proceeds from the exercise of stock options and issuance of common stock, net of issuance costs	42,753	972
Proceeds from issuance of common stock under employee stock purchase plan	1,145	1,169
Repurchase of unvested restricted common stock	(1)	(13)
Net cash provided by financing activities	45,081	150,924
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(748)	0
Change in cash, cash equivalents, and restricted cash	1,852	20,301
Cash and cash equivalents and restricted cash, beginning of period	235,123	322,976
Cash and cash equivalents, and restricted cash, end of period	236,975	343,277
Supplemental cash flow disclosure:
Cash paid for interest	2,773	0
Cash paid for income taxes	148	0
Purchase of property and equipment included in liabilities	20,629	15,770
Accrued debt issuance costs	$ 0	$ 689