Significant Accounting Policies (Policies)	6 Months Ended
Significant Accounting Policies (Policies)	Jul. 03, 2021
Accounting Policies [Abstract]
Basis of Presentation [Text Block]	Basis of Presentation These interim consolidated financial statements of SunOpta Inc. (the "Company" or "SunOpta") have been prepared in accordance with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X promulgated under the Securities Exchange Act of 1934, as amended, and in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information. Accordingly, these condensed interim consolidated financial statements do not include all of the disclosures required by U.S. GAAP for annual financial statements. In the opinion of management, all adjustments considered necessary for fair presentation have been included and all such adjustments are of a normal, recurring nature. Operating results for the quarter and two quarters ended July 3, 2021 are not necessarily indicative of the results that may be expected for the full fiscal year ending January 1, 2022 or for any other period. The interim consolidated financial statements include the accounts of the Company and its subsidiaries, and have been prepared on a basis consistent with the annual consolidated financial statements for the year ended January 2, 2021. For further information, refer to the consolidated financial statements, and notes thereto, included in the Company's Annual Report on Form 10-K for the fiscal year ended January 2, 2021.
Discontinued Operations [Policy Text Block]	Discontinued Operations As described in note 4, on December 30, 2020, the Company completed the divestiture of its organic ingredient sourcing and production business, Tradin Organic. With the divestiture, Tradin Organic qualified for reporting as discontinued operations in the consolidated financial statements of the Company. Accordingly, the operating results and cash flows of Tradin Organic for the quarter and two quarters ended June 27, 2020 have been reclassified to discontinued operations on the consolidated statements of operations and cash flows. In addition, unless otherwise indicated, the information disclosed below in these notes to the consolidated financial statements is presented on a continuing operations basis, with the comparative period information recast to reflect Tradin Organic as discontinued operations.
Fiscal Year [Policy Text Block]	Fiscal Year The fiscal year of the Company consists of a 52- or 53-week period ending on the Saturday closest to December 31. Fiscal year 2021 is a 52-week period ending on January 1, 2022, with quarterly periods ending on April 3, 2021, July 3, 2021, and October 2, 2021. Fiscal year 2020 was a 53-week period ending on January 2, 2021, with quarterly periods ending on March 28, 2020, June 27, 2020, and September 26, 2020.
Recent Accounting Pronouncements [Policy Text Block]	Recent Accounting Pronouncements In March 2020 and January 2021, the Financial Accounting Standards Board issued Accounting Standard Updates 2020-04 and 2021-01, Reference Rate Reform (Topic 848), that provide temporary optional expedients and exceptions to the U.S. GAAP guidance on contract modifications and hedge accounting to ease the financial reporting burden related to the transition away from LIBOR and other reference rates that are expected to be discontinued. The guidance in Topic 848 is effective upon issuance and can be applied prospectively for contract modifications and hedging relationships through December 31, 2022. The Company is currently evaluating the impact of the guidance and does not expect it will have a material effect on the Company’s consolidated financial statements.