Unaudited Condensed Consolidated Statements of Changes in Equity (Deficit) - USD ($) $ in Thousands	Total	Class A Common Stock	Common Stock Class A Common Stock	Common Stock Class V-1 Common Stock	Common Stock Class V-3 Common Stock	Additional Paid-in Capital - Warrants	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Noncontrolling Interest
Beginning balance (in shares) at Sep. 30, 2023			82,112,881	66,931,097	407,528,941
Beginning balance at Sep. 30, 2023	$ (2,716)		$ 8	$ 7	$ 41	$ 58,126	$ 1,254,022	$ (1,687)	$ (1,310,435)	$ (2,798)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(73,902)								(11,645)	(62,257)
Issuance of common stock under stock plans, net of shares withheld for employee taxes (in shares)			4,915,909
Issuance of common stock under stock plans, net of shares withheld for employee taxes	(3,153)						(3,103)			(50)
Issuance of common stock under employee stock purchase plan, net of shares withheld for employee taxes (in shares)			102,633
Issuance of common stock under employee stock purchase plan, net of shares withheld for employee taxes	3,500						3,500
Exchange of common stock (in shares)			7,563,865	(4,369,120)	(3,194,745)
Exchange of common stock	0		$ 3	$ (2)	$ (1)		(155)			155
Issuance of common stock in connection with equity offering (in shares)			6,500,000
Issuance of common stock in connection with equity offering	257,986		$ 1				257,985
Exercise of warrants (in shares)				15,870,411
Exercise of warrants	158,705			$ 3		(58,126)				216,828
Stock-based compensation	57,527						9,240			48,287
Other comprehensive loss	(4,304)							(686)		(3,618)
Ending balance (in shares) at Mar. 30, 2024			101,195,288	78,432,388	404,334,196
Ending balance at Mar. 30, 2024	393,643		$ 12	$ 8	$ 40	0	1,521,489	(2,373)	(1,322,080)	196,547
Beginning balance (in shares) at Dec. 30, 2023			85,106,588	81,489,643	406,512,941
Beginning balance at Dec. 30, 2023	165,770		$ 10	$ 8	$ 41		1,257,853	(1,770)	(1,313,271)	222,899
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(54,830)								(8,809)	(46,021)
Issuance of common stock under stock plans, net of shares withheld for employee taxes (in shares)			4,250,067
Issuance of common stock under stock plans, net of shares withheld for employee taxes	(3,095)						(3,095)
Issuance of common stock under employee stock purchase plan, net of shares withheld for employee taxes (in shares)			102,633
Issuance of common stock under employee stock purchase plan, net of shares withheld for employee taxes	3,500						3,500
Exchange of common stock (in shares)			5,236,000	(3,057,255)	(2,178,745)
Exchange of common stock	0		$ 1		$ (1)		381			(381)
Issuance of common stock in connection with equity offering (in shares)			6,500,000
Issuance of common stock in connection with equity offering	257,986		$ 1				257,985
Stock-based compensation	28,065						4,865			23,200
Other comprehensive loss	(3,753)							(603)		(3,150)
Ending balance (in shares) at Mar. 30, 2024			101,195,288	78,432,388	404,334,196
Ending balance at Mar. 30, 2024	393,643		$ 12	$ 8	$ 40	$ 0	1,521,489	(2,373)	(1,322,080)	196,547
Beginning balance (in shares) at Sep. 28, 2024			104,689,377	76,965,386	404,309,196
Beginning balance at Sep. 28, 2024	390,130		$ 13	$ 7	$ 40		1,523,692	(2,594)	(1,323,925)	192,897
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(39,958)								(7,401)	(32,557)
Issuance of common stock under stock plans, net of shares withheld for employee taxes (in shares)			2,939,571
Issuance of common stock under stock plans, net of shares withheld for employee taxes	(3,012)						(3,012)
Issuance of common stock under employee stock purchase plan, net of shares withheld for employee taxes (in shares)			206,664
Issuance of common stock under employee stock purchase plan, net of shares withheld for employee taxes	3,231						3,231
Exchange of common stock (in shares)			545,160	(545,160)
Exchange of common stock	0						2,106			(2,106)
Cancellation of common stock (in shares)				(196,901)
Distribution to Symbotic Holdings LLC partners	$ (1,232)									(1,232)
Issuance of common stock in connection with equity offering (in shares)	3,146,235	3,146,235
Stock-based compensation	$ 72,991						13,361			59,630
Other comprehensive loss	(576)							(104)		(472)
Ending balance (in shares) at Mar. 29, 2025			108,380,772	76,223,325	404,309,196
Ending balance at Mar. 29, 2025	421,574		$ 13	$ 7	$ 40		1,539,378	(2,698)	(1,331,326)	216,160
Beginning balance (in shares) at Dec. 28, 2024			106,521,915	76,588,618	404,309,196
Beginning balance at Dec. 28, 2024	393,925		$ 13	$ 7	$ 40		1,526,573	(2,696)	(1,327,401)	197,389
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(21,438)								(3,925)	(17,513)
Issuance of common stock under stock plans, net of shares withheld for employee taxes (in shares)			1,286,900
Issuance of common stock under employee stock purchase plan, net of shares withheld for employee taxes (in shares)			206,664
Issuance of common stock under employee stock purchase plan, net of shares withheld for employee taxes	3,231						3,231
Exchange of common stock (in shares)			365,293	(365,293)
Exchange of common stock	0						1,062			(1,062)
Distribution to Symbotic Holdings LLC partners	$ (382)									(382)
Issuance of common stock in connection with equity offering (in shares)	1,493,564	1,493,564
Stock-based compensation	$ 46,251						8,512			37,739
Other comprehensive loss	(13)							(2)		(11)
Ending balance (in shares) at Mar. 29, 2025			108,380,772	76,223,325	404,309,196
Ending balance at Mar. 29, 2025	$ 421,574		$ 13	$ 7	$ 40		$ 1,539,378	$ (2,698)	$ (1,331,326)	$ 216,160