Series B-1 Preferred Stock (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	2 Months Ended	3 Months Ended		6 Months Ended
	Mar. 03, 2023	Apr. 24, 2020	Mar. 03, 2023	Jul. 01, 2023	Jul. 02, 2022	Jul. 01, 2023	Jul. 02, 2022	May 19, 2023	Jul. 02, 2020
Temporary Equity [Line Items]
Dividends paid				$ 305	$ 609	$ 1,123	$ 1,218
Series B-1 Preferred Stock [Member]
Temporary Equity [Line Items]
Preferred Stock, Shares Issued		30,000
Preferred Stock, Value, Issued		$ 30,000
Unamortized issuance costs						300	$ 300
Series B-1 Preferred Stock [Member] | Oaktree and Engaged [Member]
Temporary Equity [Line Items]
Preferred Stock, Shares Issued		15,000
Preferred Stock, Dividend Payment Terms		Preferred dividends accrue daily on the Series B-1 preferred stock at an annualized rate of 8.0% of the liquidation preference prior to September 30, 2029, and 10.0% of the liquidation preference thereafter.
Preferred Stock, Liquidation Preference, Value									$ 30,400
Preferred Stock, Liquidation Preference Per Share									$ 1,015
Dividends paid			$ 600
Series B-1 Preferred Stock [Member] | Engaged [Member]
Temporary Equity [Line Items]
Number of shares issued for conversion preferred stock	6,089,331
Preferred stock, conversion price	$ 2.5		$ 2.5
Shares Exchanged As Percentage Of Shares Issued And Outstanding	5.30%
Preferred stock value derecognized	$ 14,100
Unamortized issuance costs	1,100
Preferred stock issuance costs	$ 100		$ 100
Redemption price per share	$ 0.00001		$ 0.00001
Dividends paid			$ 200			$ 300
Series B-1 Preferred Stock [Member] | Oaktree [Member]
Temporary Equity [Line Items]
Preferred Stock, Shares Issued				15,000		15,000
Preferred Stock, Convertible, Terms						At any time, Oaktree may exchange the Series B-1 Preferred Stock, in whole or in part, into the number of Common Shares equal to, per share of Series B-1 Preferred Stock, the quotient of the liquidation preference divided by the exchange price of $2.50. On or after April 24, 2023, SunOpta Foods may cause Oaktree to exchange all of their shares of Series B-1 Preferred Stock if the volume-weighted average price of the Common Shares during the then preceding 20 trading day period is greater than 200% of the exchange price then in effect.
Preferred Stock, Redemption Terms						In addition, at any time on or after April 24, 2025, SunOpta Foods may redeem all of the Series B-1 Preferred Stock for an amount per share equal to the value of the liquidation preference at such time, plus accrued and unpaid dividends.
Accrued unpaid dividends						$ 300
Special Shares, Series 2 [Member] | Oaktree [Member]
Temporary Equity [Line Items]
Preferred Stock, Shares Issued								2,932,453
Limit of voting rights								19.99%