CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 28, 2025	Sep. 29, 2024
Cash flows used in operating activities:
Net loss	$ (121,566)	$ (185,082)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation, accretion and amortization	26,675	37,417
Stock-based compensation	37,973	48,630
Changes in fair value of common stock warrants	(11,778)	(17,359)
Gain on bargain purchase of assets	(4,761)	0
Impairment and loss on disposal of long-lived assets	0	38,249
Interest expense (non-cash)	9,222	0
Others	1,312	174
Changes in operating assets and liabilities:
Accounts and notes receivables	(2,359)	494
Inventory	(7,247)	(827)
Prepaid expenses and other assets	445	(3,913)
Accounts payable	6,539	(10,018)
Accrued expenses and compensation	(2,781)	3,175
Deferred revenue	702	(502)
Deferred tax liability	(1,135)	(3,303)
Other liabilities	467	190
Net cash used in operating activities	(68,292)	(92,675)
Cash flows from investing activities:
Purchase of property and equipment	(17,216)	(59,830)
Payment for business acquisition	(10,000)	0
Purchases of investments	(370,133)	(31,812)
Maturities of investments	58,145	106,621
Net cash provided by (used in) investing activities	(339,204)	14,979
Cash flows from financing activities:
Proceeds from issuance of convertible senior notes and loan borrowing	360,000	4,572
Payments of debt issuance costs	(9,900)	0
Repayment of debt	(794)	(180)
Purchase of Capped Calls	(45,288)	0
Proceeds from exercise of common stock warrants	232,106	0
Payments of issuance costs related to common stock and warrant dividends	(5,995)	0
Repurchase of common stock	(58,385)	0
Proceeds from the exercise of stock options and issuance of common stock under ATM, net of issuance costs	3,133	44,285
Payroll tax payments for shares withheld upon vesting of RSUs	(4,855)	(5,601)
Proceeds from issuance of common stock under employee stock purchase plan	711	1,145
Repurchase of unvested restricted common stock	0	(4)
Net cash provided by financing activities	470,733	44,217
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(409)	1,303
Change in cash, cash equivalents, and restricted cash	62,828	(32,176)
Cash and cash equivalents and restricted cash, beginning of period	274,691	235,123
Cash and cash equivalents and restricted cash, end of period	337,519	202,947
Supplemental cash flow disclosure:
Cash paid for interest	2,971	2,951
Cash paid for income taxes	1,072	164
Purchase of property and equipment included in liabilities	8,146	14,478
Cashless warrant exercise	0	2,276
Accrued debt issuance costs	1,500	0
Accrued issuance costs related to the Warrants	$ 1,082	$ 0