JanOne Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Shareholders' Equity - Additional Information (Details)

Shareholders' Equity - Additional Information (Details)			1 Months Ended		3 Months Ended			9 Months Ended		12 Months Ended
Shareholders' Equity - Additional Information (Details)	Feb. 02, 2021 USD ($)	Jan. 29, 2021 USD ($) $ / shares shares	Aug. 31, 2020 shares	Sep. 30, 2019 USD ($) shares	Oct. 02, 2021 USD ($) $ / shares shares	Sep. 26, 2020 USD ($) shares	Mar. 28, 2020 shares	Oct. 02, 2021 USD ($) $ / shares shares	Sep. 26, 2020 USD ($) shares	Jan. 02, 2021 $ / shares shares	Apr. 30, 2021 shares	Dec. 28, 2019 shares
Shareholders Equity [Line Items]
Common stock, shares authorized (in shares)					200,000,000			200,000,000		200,000,000
Number of common stock returned to the company			71,607
Common stock, issued shares (in shares)					2,827,410			2,827,410		1,829,982
Common stock, outstanding shares (in shares)					2,827,410			2,827,410		1,829,982
Common stock par value \| $ / shares					$ 0.001			$ 0.001		$ 0.001
Options outstanding					120,500			120,500		113,900		44,400
Options granted								38,000		74,000
Share-based compensation expense \| $					$ 49,000			$ 275,000
Preferred Stock outstanding					238,729			238,729		259,729
Warrants outstanding					33,363			33,363		33,363
Warrant exercise price \| $ / shares					$ 3.40			$ 3.40		$ 3.40
Warrant expiration date								2021-11		2021-11
Stock Options
Shareholders Equity [Line Items]
Share-based compensation expense \| $						$ 46,000			$ 118,000
Unrecognized compensation expense, net of estimated forfeitures \| $					$ 34,000			$ 34,000
Unrecognized compensation expense, net of estimated forfeitures, period for recognition								2022-07
2016 Plan
Shareholders Equity [Line Items]
Options expiration date								Oct. 28, 2026
Options authorized for issuance					800,000			800,000
Options outstanding					90,000			90,000		78,000
2011 Plan
Shareholders Equity [Line Items]
Options expiration date							May 12, 2021
Options outstanding					30,500			30,500		35,900
Additional awards to be granted after adoption of 2016 plan							0
Common Stock
Shareholders Equity [Line Items]
Number of shares converted to Common Stock											420,000
Preferred Stock, Convertible, Conversion Ratio											0.05
Common Stock \| Equity Offering
Shareholders Equity [Line Items]
Common stock, shares authorized (in shares)		571,428
Common stock par value \| $ / shares		$ 0.001
Common stock purchase price per share \| $ / shares		$ 10.50
Common stock gross proceeds before deducting placement agent fees and offering expenses \| $	$ 6,000,000.0
Common Stock \| Equity Offering \| Placement Agency Agreement
Shareholders Equity [Line Items]
Percentage of cash fee gross proceeds		7.00%
Common Stock \| Equity Offering \| Maximum \| Placement Agency Agreement
Shareholders Equity [Line Items]
Gross proceeds reimbursement for accountable legal expenses \| $		$ 35,000
Series A Preferred
Shareholders Equity [Line Items]
Number of shares converted											21,000
Preferred Stock outstanding					238,729			238,729		258,729
Contractor
Shareholders Equity [Line Items]
Stock issued for services, shares				223,214					104,798
Stock issued for services, value \| $				$ 1,000,000.0					$ 351,000
Articles of Incorporation
Shareholders Equity [Line Items]
Common stock, shares authorized (in shares)						200,000,000			200,000,000