Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (604)	$ (109,143)	$ (134,568)
Changes related to cash flow hedges
Unrealized gains, net		384	1,263
Reclassification of gains to earnings		(79)	(1,568)
Net changes related to cash flow hedges		305	(305)
Currency translation adjustment	(1,614)	(2,559)	6,184
Other comprehensive earnings (loss), net of income taxes	(1,614)	(2,254)	5,879
Comprehensive loss	(2,218)	(111,397)	(128,689)
Comprehensive earnings attributable to non-controlling interests	144	207	713
Comprehensive loss attributable to SunOpta Inc.	$ (2,362)	$ (111,604)	$ (129,402)

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