Series B-1 Preferred Stock (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 30, 2024	Dec. 28, 2024	Dec. 30, 2023
Series B-1 Preferred Stock [Member] | Oaktree and Engaged [Member]
Temporary Equity [Line Items]
Preferred stock, shares issued		15,000
Preferred stock, liquidation preference, value		$ 15.2
Preferred stock, liquidation preference per share		$ 1,015
Unamortized issuance costs		$ 0.5	$ 0.6
Dividends paid	$ 0.3
Preferred stock, dividend payment terms		On April 17, 2024, the Company, SunOpta Foods and Oaktree entered into an Amending Agreement related to the elimination of the dividend rights attached to the Series B-1 Preferred Stock effective from and after December 31, 2023. The Series B-1 Preferred Stock previously paid a cumulative dividend of 8.0% per year that could be paid in-kind or in cash at the Company's option, which dividend would have increased from 8.0% to 10.0% per year and become payable only in cash at the end of the Company's third quarter in 2029. All other rights and obligations of the Company, SunOpta Foods, and Oaktree in connection with the Series B-1 Preferred Stock remain unchanged. The Company is accounting for the elimination of the dividend rights on a prospective basis.
Series B-1 Preferred Stock [Member] | Oaktree [Member]
Temporary Equity [Line Items]
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 shares of the Company's common stock ("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, while, at any time, 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.
Preferred stock, conversion price		$ 2.5
Special Shares, Series 2 [Member] | Oaktree [Member]
Temporary Equity [Line Items]
Preferred stock, shares issued		2,932,453
Limit of voting rights		19.99%